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995455 - Disclosure - Nature of Operations
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995465 - Disclosure - Basis of Presentation and Recent Accounting Pronouncements
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995475 - Disclosure - Acquisitions
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995485 - Disclosure - Revenue
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995505 - Disclosure - Restructuring Costs
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995515 - Disclosure - Income Taxes
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995525 - Disclosure - Goodwill and Other Intangible Assets
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995535 - Disclosure - Derivative Financial Instruments
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995545 - Disclosure - Debt
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995555 - Disclosure - Fair Value Measurements and Investments
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995595 - Disclosure - Supplementary Information for Certain Balance Sheet Accounts
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995625 - Disclosure - Earnings Per Share
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995635 - Disclosure - Share-based Compensation
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995645 - Disclosure - Supplemental Disclosures of Cash Flow Information
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995655 - Disclosure - Basis of Presentation and Recent Accounting Pronouncements (Policies)
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995665 - Disclosure - Acquisitions (Tables)
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995675 - Disclosure - Revenue (Tables)
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995705 - Disclosure - Goodwill and Other Intangible Assets (Tables)
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995715 - Disclosure - Derivative Financial Instruments (Tables)
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995725 - Disclosure - Debt (Tables)
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995735 - Disclosure - Fair Value Measurements and Investments (Tables)
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995755 - Disclosure - Leases (Tables)
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995765 - Disclosure - Supplementary Information for Certain Balance Sheet Accounts (Tables)
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995775 - Disclosure - Other Income/(Loss), Net (Tables)
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995785 - Disclosure - Accumulated Other Comprehensive Loss (Tables)
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995795 - Disclosure - Earnings Per Share (Tables)
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995805 - Disclosure - Supplemental Disclosures of Cash Flow Information (Tables)
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995815 - Disclosure - Nature of Operations (Details)
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995825 - Disclosure - Basis of Presentation and Recent Accounting Pronouncements (Details)
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995835 - Disclosure - Acquisitions - Narrative (Details)
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995845 - Disclosure - Acquisitions - Schedule of Fair Values of the Indentifiable Assets Acquired and Liabilities Assumed (Details)
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995855 - Disclosure - Revenue - Schedule of Disaggregation of Revenue (Details)
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995865 - Disclosure - Revenue - Schedule of Components of Interest and Other Income (Details)
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995875 - Disclosure - Revenue - Narrative (Details)
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995895 - Disclosure - Revenue - Schedule of Contract Balances (Details)
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995905 - Disclosure - Revenue - Schedule of Contract Balances (Parenthetical) (Details)
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995915 - Disclosure - Revenue - Schedule of Remaining Performance Obligations (Details)
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995925 - Disclosure - Revenue - Schedule of Remaining Performance Obligations (Details1)
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995935 - Disclosure - Segment Information - Narrative (Details)
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995945 - Disclosure - Segment Information - Revenue (Net of Reimbursable Expenses) of the Reported Segments (Details)
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995955 - Disclosure - Segment Information - Reconciliation of Information Reported by Segment to Condensed Consolidated Statement of Comprehensive Income Amounts (Details)
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995965 - Disclosure - Segment Information - Revenue and Tangible Long-lived Assets by Geographical Areas (Details)
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995975 - Disclosure - Restructuring Costs - Narrative (Details)
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995985 - Disclosure - Restructuring Costs - Rollforward of Liability Associated with Cash-based Charges (Details)
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995995 - Disclosure - Income Taxes - Narrative (Details)
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996005 - Disclosure - Goodwill and Other Intangible Assets - Components of Goodwill (Details)
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996015 - Disclosure - Goodwill and Other Intangible Assets - Changes in the Net Carrying Amount of the Components of Finite-Lived Intangible Assets (Details)
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996025 - Disclosure - Goodwill and Other Intangible Assets - Narrative (Details)
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996035 - Disclosure - Goodwill and Other Intangible Assets - Schedule of Future Estimated Amortization Expense for Amortizable Intangible Assets (Details)
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996045 - Disclosure - Derivative Financial Instruments - Narrative (Details)
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996055 - Disclosure - Derivative Financial Instruments - Schedule of Derivative Instruments Designated As Hedging Instrument Effect on Condensed Consolidated Statements of Comprehensive Income (Details)
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996065 - Disclosure - Derivative Financial Instruments - Schedule of Derivative Instruments, Effect on Condensed Consolidated Statements of Comprehensive Income (Details)
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996075 - Disclosure - Debt - Schedule of Current and Long-term Debt (Details)
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996085 - Disclosure - Debt - Narrative (Details)
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996095 - Disclosure - Fair Value Measurements and Investments - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details)
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996105 - Disclosure - Fair Value Measurements and Investments - Fair Value Liabilities Measured Using Significant Unobservable Inputs Level 3 (Details)
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996115 - Disclosure - Fair Value Measurements and Investments - Narrative (Details)
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996125 - Disclosure - Fair Value Measurements and Investments - Summarizes the Types of Holdings and Related Values (Details)
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996135 - Disclosure - Fair Value Measurements and Investments - Schedule of Assets and Liabilities Whose Carrying Values Differ From the Fair Value and are Not Measured on a Recurring Basis (Details)
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996145 - Disclosure - Retirement Benefits - Narrative (Details)
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996155 - Disclosure - Retirement Benefits - Net Periodic Benefit Cost (Details)
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996165 - Disclosure - Leases - Schedule of Amount Recorded in Consolidated Statements of Comprehensive Income (Details)
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996175 - Disclosure - Commitments and Contingencies - Narrative (Details)
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996185 - Disclosure - Supplementary Information for Certain Balance Sheet Accounts - Deferred Revenue and Accrued Expenses (Details)
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996195 - Disclosure - Supplementary Information for Certain Balance Sheet Accounts - Other Current Liabilities (Details)
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996205 - Disclosure - Supplementary Information for Certain Balance Sheet Accounts - Provision For Liabilities (Details)
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996215 - Disclosure - Other Income/(Loss), Net (Details)
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996225 - Disclosure - Other Income/(Loss), Net (Parenthetical) (Details)
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996235 - Disclosure - Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income (Loss) (Details)
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996245 - Disclosure - Accumulated Other Comprehensive Loss - Schedule of Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Details)
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996255 - Disclosure - Share-based Compensation - Narrative (Details)
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996265 - Disclosure - Earnings Per Share - Narrative (Details)
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996275 - Disclosure - Earnings Per Share - Basic and Diluted Earnings Per Share (Details)
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996285 - Disclosure - Supplemental Disclosures of Cash Flow Information (Details)
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Schedule of Cash Flow, Supplemental Disclosures [Table Text Block]
Supplemental Disclosures Regarding Cash Flow Information
Retirement Plan Type
Retirement Plan Type [Axis]
Segments
Segments [Domain]
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest, Total
Net income
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest
Restructuring Reserve, Total
Restructuring Reserve
Beginning Balance
Ending Balance
Accrued Employee Benefits, Current
Accrued retirement benefits
Schedule of Revenues from External Customers and Long-Lived Assets [Table]
Process Optimization Member
Process Optimization Member
Process Optimization [Member]
Entity Incorporation, State or Country Code
Entity Incorporation, State or Country Code
Preferred Stock, Shares Issued, Total
Preference shares, shares issued
Preferred Stock, Shares Issued
Depreciation
Depreciation Not Including Integration Component
Depreciation, not including integration component.
Statement of Financial Position Location, Balance [Domain]
Defined benefit pension plans, employer contributions
Defined Benefit Plan, Plan Assets, Contributions by Employer
Balance as of beginning of period
Balance as of end of period
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value
Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract]
Supplemental disclosure of non-cash investing and financing activities:
Restructuring and Related Activities, Description
Restructuring, description
Long-term Debt, Excluding Current Maturities, Total
Long-term debt, excluding current maturities
Long-term debt
Long-Term Debt, Excluding Current Maturities
Plan Name [Axis]
Plan Name
Equity [Abstract]
Entity Current Reporting Status
Entity Current Reporting Status
Goodwill, gross, beginning balance
Goodwill, gross, ending balance
Goodwill, Gross
Level 2 [Member]
Fair Value, Inputs, Level 2 [Member]
Commitments and Contingencies
Commitments and Contingencies Disclosure [Text Block]
Pooled / commingled funds [Member]
Commingled Funds [Member]
Commingled funds.
Cash Flow Hedging [Member]
Cash Flow Hedging [Member]
Ordinary shares, shares authorized
Common Stock, Shares Authorized
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Finite-Lived Intangible Asset, Expected Amortization, Year Four
2030
Product and Service
Product and Service [Axis]
Fair Value by Liability Class
Fair Value by Liability Class [Domain]
Document Fiscal Period Focus
Document Fiscal Period Focus
Stated interest rate
Debt Instrument, Interest Rate, Stated Percentage
Revenue from Contract with Customer [Abstract]
Entity Shell Company
Entity Shell Company
Rest of world.
Rest Of World [Member]
Rest of World [Member]
Service [Member]
Service [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance
Cash and Cash Equivalents, at Carrying Value, Beginning Balance
Cash and Cash Equivalents, at Carrying Value, Total
Cash and cash equivalents
Cash and Cash Equivalent
Dividends attributable to non-controlling interests
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders
Debt instrument maturity year
Debt Instrument Maturity Year
Debt instrument maturity year.
Common Stock, Shares, Issued, Total
Ordinary shares, shares issued
Common Stock, Shares, Issued
UNITED KINGDOM [Member]
Foreign Plan [Member]
Asset Class [Domain]
Statement [Table]
Statement [Table]
AOCL [Member]
AOCI Including Portion Attributable to Noncontrolling Interest [Member]
Minority Interest [Table]
Noncontrolling Interest [Table]
Other provisions
Other Accrued Liabilities, Noncurrent
4.550% senior notes due 2031 [Member]
Senior Notes Due 203104550 [Member]
Senior notes due 2031, 04550.
Payments to Acquire Businesses, Gross
Acquisitions, cash payment
Proceeds from Debt, Net of Issuance Costs
Proceeds from debt, net of issuance costs
Effect on Future Cash Flows, Amount
Restructuring, Expected future effects
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, after Year One through Five
Due in one year through five years carrying value
Statement [Line Items]
Statement [Line Items]
Business Acquisition, Acquiree
Business Combination [Domain]
Alexis Faber [Member]
Alexis Faber
Alexis Faber
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss)
Foreign exchange
Foreign exchange
Other income, net [Member]
Other Expense [Member]
Entity Filer Category
Entity Filer Category
Reclassification from AOCI, Current Period, Net of Tax, Attributable to Parent
(Gain)/loss reclassified from accumulated other comprehensive loss (net of income tax)
TOTAL LIABILITIES AND EQUITY
Liabilities and Equity
Debt Instrument [Line Items]
Debt Instrument [Line Items]
Long-term Debt, Current Maturities, Total
Current debt
Long-Term Debt, Current Maturities
Restructuring Type [Axis]
Operating Loss Carryforwards [Table]
Operating Loss Carryforwards [Table]
Hedging Relationship
Hedging Relationship [Axis]
Summary of Total Restructuring Costs
Restructuring and Related Costs [Table Text Block]
Revenues, Excluding Interest and Dividends
Revenues, Excluding Interest and Dividends, Total
Segment revenue excluding interest income
Derivative [Line Items]
Derivative [Line Items]
Benefits delivery and administration.
Benefits Delivery And Administration [Member]
BDA [Member]
Goodwill, net, beginning balance
Goodwill, Total
Goodwill
Goodwill, net, ending balance
Goodwill
Other Noncash Income (Expense), Total
Other, net
Other Noncash Income (Expense)
Effective Income Tax Rate Reconciliation, Percent, Total
Effective tax rate
Effective Income Tax Rate Reconciliation, Percent
Senior notes due 2028, 04500.
Senior Notes Due202804500 [Member]
4.500% senior notes due 2028 [Member]
Geographical
Geographical [Domain]
Net Operating Income of the Reported Segments
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table Text Block]
Business Combination, Achieved in Stages, Preacquisition Equity Interest in Acquiree, Percentage
Reamining controlling interest
Accounts Receivable, Allowance for Credit Loss, Ending Balance
Accounts Receivable, Allowance for Credit Loss, Beginning Balance
Allowance for doubtful debts
Accounts Receivable, Allowance for Credit Loss
Lease liabilities
Business Combination, Recognized Liability Assumed, Lease Obligation
Lease liabilities
Additional Paid in Capital, Common Stock, Ending Balance
Additional Paid in Capital, Common Stock, Beginning Balance
Additional paid-in capital
Additional Paid in Capital, Common Stock
Merger-Related Securities Litigation [Member]
Willis Towers Watson Merger Related Securities Litigation [Member]
Willis Towers Watson merger-related securities litigation.
Weighted average remaining life of amortizable intangible assets
Finite-Lived Intangible Asset, Useful Life
Weighted average remaining life of amortizable intangible assets and liabilities
Disaggregation Of Revenue [Table]
Disaggregation of Revenue [Table]
Schedule of Basic and Diluted Earnings Per Share
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Trademark and trade name [Member]
Trademarks and Trade Names [Member]
Senior notes due 2033, 05350.
Senior Notes Due 203305350 [Member]
5.350% senior notes due 2033 [Member]
Basic earnings per share
Earnings Per Share, Basic
Basic earnings per share
Disaggregation of Revenue
Disaggregation of Revenue [Table Text Block]
Repayments of Long-term Debt, Total
Repayments of debt
Repayments of Long-Term Debt
Gross unrealized gains
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Gain
Retirement Benefits
Retirement Benefits [Text Block]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Beginning Balance
Stock options outstanding
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number
Stock Issued
Fair value of Newfront ordinary shares issued
Real estate rationalization.
Real estate rationalization [Member]
Real Estate Rationalization [Member]
Revolving Credit Facility [Member]
Revolving Credit Facility [Member]
Willis Towers Watson Public Limited Company [Member]
Willis Towers Watson Public Limited Company [Member]
Willis Towers Watson public limited company.
Finite-Lived Intangible Assets Acquired
Intangible assets acquired
Preliminary values of intangible assets
Retirement Plan Type
Retirement Plan Type [Domain]
Total current liabilities
Liabilities, Current
Accounts receivable
Increase (Decrease) in Accounts Receivable
Adjustments to reconcile net income to total net cash from operating activities:
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract]
Hedging Designation
Hedging Designation [Domain]
Revenues from External Customers and Long-Lived Assets [Line Items]
Schedule of Change in Fair Value of Level 3 Liabilities
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
Fiduciary liabilities
Fiduciary Liabilities Current
Fiduciary liabilities, current.
Book-of-Business Settlements
Book-of-Business Settlements.
Book-of-business settlements
Payments of Debt Issuance Costs
Debt issuance costs
Accounts Receivable, after Allowance for Credit Loss, Noncurrent, Total
Non-current accounts receivable, net
Accounts Receivable, after Allowance for Credit Loss, Noncurrent
Segment Reconciling Items [Member]
Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member]
Consolidation Items
Consolidation Items [Domain]
Payroll and other benefits-related liabilities.
Payroll and other benefits-related liabilities
Payroll and other benefits-related liabilities
Entity Small Business
Entity Small Business
Hedging Designation
Hedging Designation [Axis]
Retained Earnings (Accumulated Deficit), Ending Balance
Retained Earnings (Accumulated Deficit), Beginning Balance
Retained Earnings (Accumulated Deficit), Total
Retained Earnings (Accumulated Deficit)
Accumulated deficit
Nature of Operations
Nature of Operations [Text Block]
Allowance for credit losses
Debt Securities, Held-to-Maturity, Allowance for Credit Loss
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Ending Balance
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Beginning Balance
Debt Securities, Held-to-Maturity, Allowance for Credit Loss, Total
Allowance for credit losses
Compensation And Retirement Disclosure [Table]
Compensation And Retirement Disclosure [Table]
Compensation and retirement disclosure.
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]
Consulting [Member]
Consulting [Member]
Consulting.
Settled Litigation [Member]
Settled Litigation [Member]
Share-based Compensation
Share-Based Payment Arrangement [Text Block]
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Other (Loss)/Income [Member]
Other (loss)/income.
Other Income/(loss) [Member]
Leases [Abstract]
Weighted Average Number Diluted Shares Outstanding Adjustment, Total
Dilutive effect of potentially issuable shares (shares)
Weighted Average Number of Shares Outstanding, Diluted, Adjustment
Contract with Customer, Liability, Total
Deferred revenue
Contract with Customer, Liability
Amendment Flag
Amendment Flag
Product and Service
Product and Service [Domain]
Loss Contingencies [Line Items]
Loss Contingencies [Line Items]
Other Significant Noncash Transaction, Value of Consideration Given
Fair value of Newfront ordinary shares issued
Schedule of Held-to-Maturity Securities [Line Items]
Delayed Draw Term Loan (DDTL) [Member]
Delayed Draw Term Loan [Member]
Delayed Draw Term Loan Facility [Member]
LIABILITIES AND EQUITY
Liabilities and Equity [Abstract]
Entity Address, Postal Zip Code
Entity Address, Postal Zip Code
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation
Net cash used in operating activities
Segment Reporting, CODM, Profit (Loss) Measure, How Used, Description
Shares outstanding [Member]
Common Stock [Member]
Common Stock [Member]
Hedging Relationship
Hedging Relationship [Domain]
Pension benefits assets
Assets for Plan Benefits, Defined Benefit Plan
Unallocated, net
Other Operating Income (Expense), Net
Delaware Action [Member]
Delaware Action [Member]
Delaware Action.
Foreign Exchange Option [Member]
Foreign exchange options [Member]
Portion at Fair Value Measurement [Member] [Default]
Portion at Fair Value Measurement [Member]
Entity Address, Address Line One
Entity Address, Address Line One
Fair Value Hierarchy and NAV
Fair Value Hierarchy and NAV [Axis]
EARNINGS PER SHARE
Earnings Per Share [Abstract]
Human capital and benefits.
HCB [Member]
Human Capital And Benefits [Member]
Supplemental disclosures of cash flow information:
Supplemental Cash Flow Information [Abstract]
Derivative Asset, Total
Derivative financial instruments
Derivative Asset
Derivative asset, fair value
Goodwill and Other Intangible Assets
Goodwill and Intangible Assets Disclosure [Text Block]
Foreign currency translation
Adjustments To Additional Paid In Capital Foreign Currency Translation Gain Loss
Adjustments to additional paid in capital, foreign currency translation gain (loss).
Statement of Financial Position Location, Balance [Axis]
Fair Value Measurements, Nonrecurring [Table Text Block]
Schedule of Assets and Liabilities Whose Carrying Values Differ From the Fair Value and are Not Measured on a Recurring Basis
Right-of-use assets
Operating Lease, Right-of-Use Asset
Balance Sheet Date
Balance Sheet Date [Domain]
Balance sheet date.
Net Income (Loss) Attributable to Noncontrolling Interest, Total
Income attributable to non-controlling interests
Net Income (Loss) Attributable to Noncontrolling Interest
Business Combination, Recognized Asset Acquired, Other Asset, Current
Right-of-use assets
Document Type
Document Type
Percentage of ownership by parent
Subsidiary, Ownership Percentage, Parent
Entity Central Index Key
Entity Central Index Key
Realized Gain (Loss), Foreign Currency Transaction, before Tax
Foreign exchange loss
Nontrade Receivables, Current
Nontrade Receivables, Current, Total
Note receivable
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Excluding Exchange Rate Effect, Including Discontinued Operation
Decrease in cash, cash equivalents and other restricted cash
DECREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH
DECREASE IN CASH, CASH EQUIVALENTS AND RESTRICTED CASH
Antidilutive securities excluded from computation of earnings per share
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount
Stock Repurchased and Retired During Period, Shares
Shares repurchased (in shares)
Ordinary shares, nominal value
Common Stock, Par or Stated Value Per Share
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Net current-period other comprehensive (loss)/income
Net other comprehensive (loss)/income
Business Combination, Recognized Asset Acquired, Deferred Tax Asset
Deferred tax assets
Non-cash lease expense
Operating Lease, Right-of-Use Asset, Periodic Reduction
Goodwill [Line Items]
Goodwill [Line Items]
Other liabilities
Increase (Decrease) in Other Operating Liabilities
Increase (Decrease) in Other Operating Liabilities, Total
Retirement Plan Sponsor Location
Retirement Plan Sponsor Location [Domain]
Total WTW shareholders' equity [Member]
Parent [Member]
Other Legislation
Other Legislation [Policy Text Block]
Other legislation
Rollforward of liability associated with cash-based charges.
Rollforward of liability associated with cash-based charges [Table Text Block]
Rollforward of Liability Associated with Cash-based Charges
Not Issued [Member]
Not Issued [Member]
Not Issued.
Debt Disclosure [Abstract]
Foreign currency translation [Member]
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Derivative [Table]
Derivative [Table]
Supplemental Cash Flow Elements [Abstract]
Fair Value [Member]
Estimate of Fair Value Measurement [Member]
Hedge Funds [Member]
Marketable Securities, Total
Mutual funds / exchange traded funds
Marketable Securities
Derivative, notional amount
Derivative, Notional Amount
Ownership
Ownership [Domain]
Current Fiscal Year End Date
Current Fiscal Year End Date
Current Fiscal Year End Date
Debt Instrument [Table]
Schedule of Long-Term Debt Instruments [Table]
Schedule of Other Non-current Liabilities
Other Noncurrent Liabilities [Table Text Block]
Document Quarterly Report
Document Quarterly Report
Other non-current assets
Business Combination, Recognized Asset Acquired, Other Asset, Noncurrent
Restricted Cash and Cash Equivalents [Axis]
Other Cost and Expense, Operating, Total
Other operating expenses
Other Cost and Expense, Operating
Client relationships [Member]
Customer Relationships [Member]
Customer Relationships [Member]
Liability, Pension and Other Postretirement and Postemployment Benefits, Current
Accrued 401(k) contributions
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Ending Balance
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number, Beginning Balance
Restricted share units outstanding
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number
Comprehensive Income (Loss), Net of Tax, Attributable to Parent
Comprehensive income attributable to WTW
Geographical
Geographical [Axis]
Additional non-controlling interests
Noncontrolling Interest, Increase from Business Combination
Contract with Customer, Liability, Revenue Recognized
Contract with Customer, Liability, Revenue Recognized
Fiduciary assets
Funds Held for Clients
Stockholders' Equity Attributable to Noncontrolling Interest, Ending Balance
Stockholders' Equity Attributable to Noncontrolling Interest, Beginning Balance
Stockholders' Equity Attributable to Noncontrolling Interest, Total
Non-controlling interests
Equity, Attributable to Noncontrolling Interest
Total interest and other income
Interest and other income
Interest and Other Income
Performance-Based Stock Units [Member]
Performance Shares [Member]
Billed Receivable, Current
Billed Contracts Receivable
Billed receivables, net of allowance for doubtful accounts of $34 million and $30 million
Other Assets, Noncurrent, Total
Other non-current assets
Other Assets, Noncurrent
Revenue [Member]
Revenue [Member]
Revenue member.
Revenue:
Segment Reconciliation [Abstract]
Antidilutive Securities
Antidilutive Securities [Axis]
Operating Loss Carryforwards [Line Items]
Operating Loss Carryforwards [Line Items]
Business Combination, Recognized Asset Acquired, Prepaid Expense and Other Asset, Current
Prepaid and other current assets
Basis of Presentation and Recent Accounting Pronouncements
Basis of Presentation and Significant Accounting Policies [Text Block]
Other [Member]
Product and Service, Other [Member]
Contingent and deferred consideration on acquisitions
Business Combination Contingent Consideration Liability And Deferred Consideration Current
Business combination contingent consideration liability and deferred consideration current.
Pension Expense (Reversal of Expense), Noncash
Non-cash pre-tax pension settlement charge
Total [Member]
AOCI Attributable to Parent [Member]
Derivative Liability, Total
Derivative financial instruments
Derivative liability, fair value
Derivative Liability
Finite-Lived Intangible Assets, Major Class Name
Finite-Lived Intangible Assets, Major Class Name [Domain]
4.650% senior notes due 2027 [ Member]
Senior Notes Due 202704650 [Member]
Senior notes due 202704650 [Member].
Cash and Cash Equivalents [Domain]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Dilutive effect of potentially issuable shares (USD per share)
Dilutive Securities Effect On Basic Earnings Per Share
Dilutive securities, effect on basic earnings per share.
Entity Number of Employees
Number of employees employed
Debt Securities, Held-to-Maturity [Table]
Business Combination, Consideration Transferred
Business Combination, Consideration Transferred, Total
Contingent consideration fair value
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill
Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Excluding Goodwill, Total
Intangible assets
Debt Instrument, Maturity Date
Maturity date
Minimum [Member]
Minimum [Member]
Minimum [Member]
Financial Instrument [Axis]
Broking [Member]
Broking [Member]
Broking.
Aon Plc [Member]
Aon Plc [Member]
Aon plc.
Reconciliation Of Operating Profit Loss From Segments To Consolidated [Table]
Reconciliation of Operating Profit (Loss) from Segments to Consolidated [Table]
Amortization of Intangible Assets, Total
Amortization
Amortization
Amortization
Amortization of Intangible Assets
Level 3 [Member]
Fair Value, Inputs, Level 3 [Member]
Nonrecurring [Member]
Fair Value, Nonrecurring [Member]
Liabilities:
Liabilities, Fair Value Disclosure [Abstract]
Segment Reporting [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]
Restructuring and Related Activities Disclosure [Text Block]
Restructuring Costs
Proceeds from Issuance of Long-Term Debt and Capital Securities, Net
Proceeds from Issuance of Long-Term Debt and Capital Securities, Net, Total
Borrowing of other debt
Stock Repurchased and Retired During Period, Value
Shares repurchased
Other Current Liabilities [Table Text Block]
Schedule of Other Current Liabilities
Deferred Compensation Plan Assets
Deferred compensation plans
Equity, beginning balance (in shares)
Equity, ending balance (in shares)
Shares, Outstanding
Sublease income
Sublease Income
Accounts receivable, net
Accounts receivable, net
Accounts Receivable, after Allowance for Credit Loss, Current
Contract with Customer, Asset and Liability
Schedule of Accounts, Notes, Loans and Financing Receivable [Table Text Block]
Other Income
Other income
COMMITMENTS AND CONTINGENCIES
Commitments and Contingencies
Service cost
Defined Benefit Plan, Service Cost
Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture, Total
Issuance of shares under employee stock compensation plans (in shares)
Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture
Provision for doubtful receivables from clients
Accounts Receivable, Credit Loss Expense (Reversal)
Deferred Compensation Liability, Current, Total
Deferred Compensation Liability, Current
Deferred compensation plan liabilities
Debt Instrument, Basis Spread on Variable Rate
Interest rate spread
Components of Goodwill
Schedule of Goodwill [Table Text Block]
Expected decrease in liability for uncertain tax position
Decrease in Unrecognized Tax Benefits is Reasonably Possible
Contingent consideration [Member]
Obligations [Member]
Non Rule 10b51 Arr Modified Flag
Non rule 10b51 arr modified flag.
Contingent Consideration Related to Acquisition [Member]
Contingent consideration related to acquisition.
Contingent Consideration Related to Acquisition [Member]
Payments to Acquire Equity Method Investments
Contributions to investments in associates
Acquisitions, cash payment
NET INCOME
NET INCOME
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest
Business Combination, Recognized Asset Acquired, Cash and Cash Equivalent
Cash and cash equivalents
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss
Debt Securities, Held-to-Maturity, Amortized Cost, before Allowance for Credit Loss, Total
Amortized cost basis
Non-Fiduciary.
Non-Fiduciary [Member]
Long-Term Debt, Type [Domain]
Loss Contingencies [Table]
Loss Contingencies [Table]
Weighted Average Number of Shares Outstanding, Basic, Total
Basic average number of shares outstanding (shares)
Weighted Average Number of Shares Outstanding, Basic
Goodwill, Acquired During Period
Goodwill acquired
Andrew Krasner [Member]
Andrew Krasner [Member]
Andrew Krasner
Restrictions on Cash and Cash Equivalents [Table]
Interest Income, Operating and Nonoperating
Interest Income, Operating and Nonoperating, Total
Interest income
4.400% senior notes due 2026 [Member]
Senior Notes Due202604400 [Member]
Senior notes due 2026, 04400.
December Thirty One Two Thousand And Twenty Five [Member]
December thirty one two thousand and twenty five.
Dec 31, 2025 [Member]
Senior Notes Due 203605150 [Member]
Senior notes due 2036, 05150.
5.150% senior notes due 2036 [Member]
Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table]
Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table]
Certificates of deposit and term deposits.
Certificates of Deposit And Term Deposits [Member]
Certificates of Deposit/Term Deposit [Member]
Segments
Segments [Axis]
Business Combination Integration Related Transaction Costs
Business combination integration related transaction costs.
Transaction and transformation, net
Transaction and integration expenses
Other Foreign Plans [Member]
Other Foreign Plans [Member]
Other foreign plans.
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash, Total
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash
Net periodic cost of defined benefit pension plans
Long-Term Debt
Long-Term Debt, Total
Long term debt principal amount
Total WTW shareholders' equity
Stockholders' equity attributable to parent, beginning balance
Stockholders' equity attributable to parent, ending balance
Equity, Attributable to Parent
Defined benefit plan, estimated future employer additional contributions, remainder of fiscal year
Defined Benefit Plan, Expected Future Employer Contributions, Remainder of Fiscal Year
Preference shares, nominal value (USD per share)
Preferred Stock, Par or Stated Value Per Share
Reimbursable expenses and other
Reimbursable Expenses And Other
Reimbursable expenses and other.
Basis of Presentation
Basis of Accounting, Policy [Policy Text Block]
Proposed Combination with AON Plc [Member]
Proposed Combination With A O N Plc [Member]
Proposed combination with AON plc.
Statement of Stockholders' Equity [Abstract]
Gross unrealized losses
Gross unrealized losses
Debt Securities, Held-to-Maturity, Accumulated Unrecognized Loss
Type of Restructuring [Domain]
Finite-Lived Intangible Asset, Expected Amortization, Remainder of Fiscal Year
Remainder of 2026
Cumulative costs.
Cumulative Costs [Member]
Cumulative Costs [Member]
Treasury Stock Common [Member]
Treasury Stock, Common [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Disclosure [Line Items]
Foreign Currency Transaction Gain (Loss), before Tax, Total
Gain (Loss), Foreign Currency Transaction, before Tax
Non-cash foreign exchange (gain)/loss
OCI, before Reclassifications, Net of Tax, Attributable to Parent
Other comprehensive (loss)/income before reclassifications
Entity Address, Address Line Two
Entity Address, Address Line Two
Fair Value Disclosures [Text Block]
Fair Value Measurements and Investments
Debt securities
Payments to Acquire Held-to-Maturity Securities
United States [Member]
UNITED STATES
Defined pension and post-retirement benefit costs [Member]
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Non-controlling interests [Member]
Noncontrolling Interest [Member]
Debt Instrument, Name
Debt Instrument, Name [Domain]
Fair Value Inputs, Discount Rate [Member]
Measurement Input, Discount Rate [Member]
Income (Loss) from Equity Method Investments
Interests in earnings of associates, net of tax
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Segment Reporting, CODM, Individual Title and Position or Group Name [Extensible Enumeration]
Segment Reporting, Other Segment Item, Amount
Other segment expense
Plan Name
Plan Name [Domain]
Newfront Insurance Holdings Inc [Member]
Newfront Insurance Holdings Inc.
Newfront Insurance Holdings, Inc
Software [Member]
Software and Software Development Costs [Member]
Developed software
Other assets
Increase (Decrease) in Other Operating Assets, Total
Increase (Decrease) in Other Operating Assets
Payments
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Deferred Revenue And Accrued Expenses
Business combination, recognized identifiable assets and liability assumed, deferred revenue and accrued expenses.
Deferred revenue and accrued expenses
Interest Expense, Total
Interest expense
Interest Expense, Operating and Nonoperating
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]
Credit Facility [Axis]
Credit Facility
6.125% senior notes due 2043 [Member]
Senior Notes Due204306125 [Member]
Senior notes due 2043, 06125.
Restructuring Plan [Axis]
Pension Plan [Member]
Pension Plan [Member]
Disposal Group Name
Disposal Group Name [Domain]
Senior Unsecured Long Term Debt [Member]
Senior Unsecured Long Term Debt [Member]
Senior unsecured long term debt.
Foreign exchange contracts [Member]
Foreign Exchange Contract [Member]
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Fiduciary liabilities
Business combination recognized identifiable assets acquired and liabilities assumed, fiduciary liabilities.
Fiduciary liabilities
Entity Address, City or Town
Entity Address, City or Town
Number of reportable segments
Number of Reportable Segments
Security Exchange Name
Security Exchange Name
Credit Facility
Credit Facility [Domain]
Europe [Member]
Europe [Member]
Counterparty Name
Counterparty Name [Axis]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest
INCOME FROM OPERATIONS BEFORE INCOME TAXES AND INTEREST INEARNINGS OF ASSOCIATES
Income from operations before income taxes and interest in earnings of associates
Ordinary shares and APIC [Member]
Common Stock Including Additional Paid in Capital [Member]
Rule 10b51 Arr Modified Flag
Rule 10b51arr modified flag.
Measurement Input Type
Measurement Input Type [Domain]
Antidilutive Securities, Name
Antidilutive Securities, Name [Domain]
Retirement Plan Sponsor Location
Retirement Plan Sponsor Location [Axis]
Cushon [Member]
Cushon member.
Cushon
CRB [Member]
Corporate Risk And Broking [Member]
Corporate risk and broking.
Number of countries in which entity operates (more than 140)
Number of Countries in which Entity Operates
Number of countries in which entity operates (more than 140)
Divested Businesses
Divested Businesses [Member]
Divested Businesses [Member]
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Total
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, BEGINNING OF PERIOD
CASH, CASH EQUIVALENTS AND RESTRICTED CASH, END OF PERIOD
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation
Cash, cash equivalents and restricted cash
Measurement Basis
Measurement Basis [Axis]
Statistical Measurement
Statistical Measurement [Domain]
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net, Total
Derivative Instruments Not Designated as Hedging Instruments, Gain (Loss), Net
(Loss)/gain recognized in income
Total current assets
Assets, Current
Share-Based Payment Arrangement, Expense
Share-based compensation
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block]
Fiduciary assets.
Fiduciary Assets [Member]
Document Period End Date
Document Period End Date
Other Income and Expenses [Abstract]
Fair Value Hierarchy and NAV
Fair Value Hierarchy and NAV [Domain]
Defined Contribution Plan, Cost
Defined contribution plan expenses
Thereafter
Finite Lived Intangible Assets Amortization Expense After Year Four
Finite lived intangible assets amortization expense after year four.
Outsourced administration [Member]
Outsourced Administration [Member]
Outsourced administration.
Acquired Finite-Lived Intangible Assets, Weighted Average Useful Life
Weighted-average expected lives of intangible assets
Statement of Financial Position [Abstract]
Restricted Stock Units (RSUs) [Member]
Restricted Share Units [Member]
Restricted Stock Units [Member]
Risk And Uncertainties Policy [Text Block]
Risk and uncertainties.
Risks and Uncertainties of the Economic Environment Caused by the Pandemic
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Line Items]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Loss Contingency Nature
Loss Contingency Nature [Axis]
Line of Credit [Member]
Line of Credit [Member]
Loss Contingency, Nature
Loss Contingency, Nature [Domain]
Disposal Group, Not Discontinued Operation, Gain (Loss) on Disposal
Gain on disposal of operations
Class of Stock
Class of Stock [Axis]
Segment Reporting Reconciling Item For Operating Profit Loss From Segment To Consolidated [Line Items]
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
IRELAND
Ireland [Member]
Not Designated as Hedging Instrument [Member]
Nondesignated [Member]
Not Designated as Hedging Instrument [Member]
TOTAL LIABILITIES
Liabilities
Financial Instruments [Domain]
Restructuring and Related Cost, Incurred Cost
Restructuring, Cost incurred
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent
Gain/(loss) reclassified from Accumulated OCL into income (effective element)
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Maturity, Allocated and Single Maturity Date, Year One
Due in one year or less carrying value
Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, Year One
Due in one year or less fair value
Employee Share Purchase Plan [Member]
Employee share purchase plan.
Employee Share Purchase Plan [Member]
Derivative Liability, Statement of Financial Position [Extensible Enumeration]
Expected return on plan assets
Defined Benefit Plan, Expected Return (Loss) on Plan Assets
Restricted Cash and Cash Equivalent Item [Line Items]
Dividends Payable, Current
Dividends payable
Finite-Lived Intangible Assets, Gross, Total
Finite-lived intangible assets, gross carrying amount
Finite-Lived Intangible Assets, Gross
Diluted average number of shares outstanding (shares)
Weighted Average Number of Shares Outstanding, Diluted
Diluted average number of shares outstanding (shares)
Entity File Number
Entity File Number
Dividends paid
Payments of Ordinary Dividends, Common Stock
UNITED STATES [Member]
Domestic Plan [Member]
Schedule of Derivative Instruments Designated/Nondesignated As Hedging Instrument Effect on Condensed Consolidated Statements of Comprehensive Income
Derivative Instruments, Gain (Loss) [Table Text Block]
Cover [Abstract]
Measurement Input Type
Measurement Input Type [Axis]
Other employee-related liabilities
Other Employee-related Liabilities, Current
Total prepaid and other current assets
Prepaid and other current assets
Prepaid Expense and Other Assets, Current
Income taxes payable
Taxes Payable, Current, Total
Taxes Payable, Current
Accrued vacation
Other Deferred Compensation Arrangements, Liability, Current
Business Combination, Recognized Liability Assumed, Other Liability, Current
Other current liabilities
Other current liabilities
Reclassification from AOCI, Current Period, Tax, Total
Reclassification from AOCI, Current Period, Tax
Reclassification from AOCI, Current Period, Tax
Supplementary Information for Certain Balance Sheet Accounts
Supplemental Balance Sheet Disclosures [Text Block]
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest
INCOME FROM OPERATIONS BEFORE INCOME TAXES AND INTEREST IN EARNINGS OF ASSOCIATES
Carl Hess [Member]
Carl Hess
Carl Hess
Number of operating segments
Number of Operating Segments
3.875% senior notes due 2049 [Member]
Senior Notes Due204903875 [Member]
Senior notes due 2049, 03875.
Segment Information
Segment Reporting Disclosure [Text Block]
Fair value inputs, weighted-average discount rate
Alternative Investment, Measurement Input
Proceeds from (Payments for) Securities Purchased under Agreements to Resell
Proceeds from (Payments for) Securities Purchased under Agreements to Resell, Total
Net sales/(purchases) of available-for-sale securities
Derivative instruments [Member]
AOCI, Derivative Qualifying as Hedge, Excluded Component, Parent [Member]
Minority Interest [Line Items]
Noncontrolling Interest [Line Items]
Stock Issued During Period, Shares, Acquisitions
Acquisition of Newfront (in shares)
Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested, Number of Shares
Shares issued under ESPP
Number of ordinary shares vested
Share-Based Compensation Arrangement by Share-Based Payment Award, Shares Issued in Period
Shares issued
Finite-Lived Intangible Assets, Net, Ending Balance
Finite-Lived Intangible Assets, Net, Beginning Balance
Total
Finite-lived intangible assets, net amount
Finite-Lived Intangible Assets, Net
Share-based compensation and net settlements
Adjustments To Additional Paid In Capital Sharebased Compensation And Net Settlements
Adjustments to additional paid in capital, sharebased compensation and net settlements.
Transaction and Integration Expense [Member]
Transaction and integration expense.
Transaction and Integration Expense [Member]
Restructuring Charges, Total
Restructuring Charges
Restructuring costs
Charges incurred
Restructuring costs
Recent Accounting Pronouncements
New Accounting Pronouncements, Policy [Policy Text Block]
Claims, lawsuits and other proceedings
Estimated Litigation Liability, Noncurrent
Ownership
Ownership [Axis]
Accumulated Other Comprehensive Loss
Comprehensive Income (Loss) Note [Text Block]
Depreciation, Total
Depreciation
Depreciation
Carrying Value [Member]
Reported Value Measurement [Member]
R and B segment.
R and B Segment [Member]
R&B Segment [Member]
Corporate Segment [Member]
Corporate Segment [Member]
Corporate [Member]
Common Stock, Shares, Outstanding, Ending Balance
Common Stock, Shares, Outstanding, Beginning Balance
Ordinary shares, shares outstanding
Common Stock, Shares, Outstanding
Current lease liabilities
Operating Lease, Liability, Current
Other Restricted Assets, Current
Fiduciary funds (included in fiduciary assets)
Revenue, Remaining Performance Obligation, Amount
Revenue, Remaining Performance Obligation, Amount
Revenue, Remaining Performance Obligation
Amortization of prior service credit
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)
Document Transition Report
Document Transition Report
Business Combination, Contingent Consideration [Table]
Short-Term Investments
Short-Term Investments, Total
Short-term investment (held to maturity)
Total segment expense
Operating Expenses
Long-term service contract Period.
Long Term Service Contract Period
Long term service contract Period
Debt Securities, Held-to-Maturity, Fair Value
Aggregate fair value
Aggregate fair value
Portion of pension and OPEB obligation attributed to disclosed plans (as a percent)
Defined Benefit Plans Percentage Of Obligation From Plans
Defined benefit plans, percentage of obligation from plans.
Payments for Repurchase of Common Stock
Repurchase of shares
Repurchase of shares
Net periodic pension and postretirement benefit credits
Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component
Litigation Status
Litigation Status [Axis]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest, Total
Comprehensive income before non-controlling interests
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest
Liability, Defined Benefit Plan, Noncurrent, Total
Liability for pension benefits
Liability, Defined Benefit Plan, Noncurrent
Statement of Cash Flows [Abstract]
Amortization
Cost, Amortization
Assets:
Assets, Fair Value Disclosure [Abstract]
Business Combination, Contingent Consideration, Range of Outcomes, Maximum, Amount
Contingent consideration, amount
Derivative Asset, Statement of Financial Position [Extensible Enumeration]
Payments to Acquire Businesses, Net of Cash Acquired, Total
Acquisitions of operations, net of cash acquired
Payments to Acquire Businesses, Net of Cash Acquired
Fiduciary assets
Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed, Fiduciary Assets
Business combination recognized identifiable assets acquired and liabilities assumed, fiduciary assets.
Finite Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets [Line Items]
Earnings Per Share
Earnings Per Share [Text Block]
Performance Targets [Member]
Performance targets.
Performance Targets
NET INCOME ATTRIBUTABLE TO WTW
Net income attributable to WTW
2.950% senior notes due 2029 [Member]
Senior Notes Due202902950 [Member]
Senior notes due 2029, 02950.
Operating lease cost
Operating Lease, Cost
Intangible Assets, Net (Excluding Goodwill), Total
Other intangible assets, net
Intangible Assets, Net (Excluding Goodwill)
Accrual for Taxes Other than Income Taxes, Current
Other taxes payable
ASSETS
Assets [Abstract]
Due in greater than five years fair value
Held to Maturity Securities Debt Maturities After Five Years Fair Value
Held to maturity securities debt maturities after five years fair value.
Number of shares receivable upon acquisition
Number Of Shares Receivable Upon Acquisition
Number of shares receivable upon acquisition.
Repayments of Debt
Repayment of debt
Restructuring and Related Activities [Abstract]
Document Fiscal Year Focus
Document Fiscal Year Focus
Other
Miscellaneous Other Non Operating Income Expense
Miscellaneous other non-operating income expense.
Schedule of Accumulated Other Comprehensive Income (Loss)
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract]
CASH FLOWS USED IN INVESTING ACTIVITIES
Retirement Benefits [Abstract]
IRR [Member]
Investment Risk And Reinsurance [Member]
Investment, risk and reinsurance.
Schedule of Net Periodic Benefit Cost
Schedule of Net Benefit Costs [Table Text Block]
Obligations assumed
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases
Tax exempt gain on sale
Preliminary pre-tax gain on sale
Gain on disposal
Gain on disposal of operations
Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture, Total
Issuance of shares under employee stock compensation plans
Shares Issued, Value, Share-Based Payment Arrangement, after Forfeiture
Restructuring Cost and Reserve [Line Items]
Finite-Lived Intangible Asset, Expected Amortization, Year One
2027
Defined Benefit Plan, Plan Assets, Payment for Settlement
Defined Benefit Plan Purchase of Annuity Contract
Fair Value Disclosures [Abstract]
Commitments and Contingencies Disclosure [Abstract]
Stock Issued During Period, Value, Acquisitions
Acquisition of Newfront
Capital Expenditures.
Capital Expenditures [Member]
Capital Expenditures [Member]
North America [Member]
North America [Member]
Cash Flow, Supplemental Disclosures [Text Block]
Supplemental Disclosures of Cash Flow Information
Contract with Customer, Asset, after Allowance for Credit Loss, Current, Total
Contract asset, Current
Contract with Customer, Asset, after Allowance for Credit Loss, Current
Current contract assets
Net proceeds from fiduciary funds held for clients
Net Proceeds from Fiduciary Funds Held for Clients
Net proceeds from fiduciary funds held for clients.
Debt Instrument
Debt Instrument [Axis]
Derivative Instrument
Derivative Instrument [Axis]
Interest cost
Defined Benefit Plan, Interest Cost
Share-Based Payment Arrangement [Abstract]
Revenue
Revenues
Total segment revenue
Total revenue
Cash Provided by (Used in) Investing Activity, Including Discontinued Operation
Net cash used in investing activities
Senior notes due 2054, 05900.
Senior Notes Due205405900 [Member]
5.900% senior notes due 2054 [Member]
Title of 12(b) Security
Title of 12(b) Security
Schedule Of Segment Reporting Information By Segment [Table]
Schedule of Segment Reporting Information, by Segment [Table]
Derivative Financial Instruments
Derivative Instruments and Hedging Activities Disclosure [Text Block]
Income Taxes
Income Tax Disclosure [Text Block]
Other non-current liabilities
Other Liabilities, Noncurrent
Total other non-current liabilities
Restructuring Plan [Domain]
Changes in operating assets and liabilities, net of effects from purchase of subsidiaries:
Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract]
Debt Securities, Held-to-Maturity, Fair Value, Maturity, Allocated and Single Maturity Date, after Year One Through Five
Due in one year through five years fair value
Income Tax Disclosure [Abstract]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table]
Fair Value, Recurring and Nonrecurring [Table]
Interest Income.
Interest income
Interest Income
Projected annual cost savings by end of 2024.
Projected Annual Cost Savings by End of 2024 [Member]
Projected Annual Cost Savings by End of 2024 [Member]
Dispositions [Abstract]
Dispositions.
United Kingdom [Member]
UNITED KINGDOM
Measurement Frequency
Measurement Frequency [Domain]
Income Statement Location
Statement of Income Location, Balance [Axis]
Senior Notes [Member]
Senior Notes [Member]
Senior Notes
Trading Symbol
Trading Symbol
Schedule Of Finite Lived Intangible Assets [Table]
Intangible Asset, Finite-Lived [Table]
Business Combination Integration Related Costs Credits
Business combination integration related costs credits.
Transaction and integration expenses
Changes in the Net Carrying Amount of the Components of Finite-Lived Intangible Assets
Schedule of Finite-Lived Intangible Assets [Table Text Block]
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract]
CASH FLOWS (USED IN)/FROM FINANCING ACTIVITIES
Federal Action.
Federal Action [Member]
Federal Action [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage
Commitment fee percentage
Recurring [Member]
Fair Value, Recurring [Member]
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Other Restructuring [Member]
Other [Member]
Equity Components
Equity Components [Axis]
Debt Securities, Held-to-Maturity [Table Text Block]
Summarizes the Types of Holdings and Related Values
Equity Component
Equity Component [Domain]
Asset Class [Axis]
Accrued discretionary and incentive compensation
Accrued Discretionary And Incentive Compensation
Carrying value as of the balance sheet date of obligations incurred and payable for incentive compensation awarded to employees and directors or earned by them based on the terms of one or more relevant arrangements.
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement, Total
Settlements
Pension settlement charge
Goodwill and Intangible Assets Disclosure [Abstract]
Liabilities for uncertain tax positions
Liability for Uncertainty in Income Taxes, Noncurrent
Due in greater than five years carrying value
Held to Maturity Securities Debt Maturities After Five Years Net Carrying Amount
Held to maturity securities debt maturities after five years net carrying amount.
Business Combination, Recognized Asset Acquired and Liability Assumed [Table Text Block]
Schedule of Fair Values of the Indentifiable Assets Acquired and Liabilities Assumed
Business Acquisition
Business Combination [Axis]
Contingent consideration
Obligations, Fair Value Disclosure
Provisions
Increase Decrease In Provision For Liabilities
Increase decrease in provision for liabilities.
Revenue Remaining Performance Obligation Expected Timing Of Satisfaction [Table]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table]
Above Target Performance [Member]
Above target performance.
Above Target Performance
Benefit from deferred income taxes
Deferred Income Tax Expense Benefit Including Discontinued Operations
Deferred income tax expense benefit including discontinued operations.
Maximum [Member]
Maximum [Member]
Designated [Member]
Designated as Hedging Instrument [Member]
Designated as Hedging Instrument [Member]
Total provision for liabilities
Provision for liabilities
Provision For Liabilities Non Current
Provision for liabilities non current.
Statistical Measurement
Statistical Measurement [Axis]
Finite-Lived Intangible Assets, Accumulated Amortization
Finite-lived intangible assets, accumulated amortization
Litigation Status
Litigation Status [Domain]
Goodwill [Roll Forward]
Goodwill [Roll Forward]
Total equity
Equity, beginning balance
Equity, ending balance
Equity, Including Portion Attributable to Noncontrolling Interest
Schedule of Future Estimated Amortization Expense for Amortizable Intangible Assets
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]
Loss Contingency, Estimated Recovery from Third Party
Business interruption losses coverage
Preference shares, shares authorized
Preferred Stock, Shares Authorized
Fiduciary [Member]
Fiduciary.
Total deferred revenue and accrued expenses
Deferred revenue and accrued expenses
Deferred Revenue And Accrued Liabilities Current
Deferred revenue and accrued liabilities current.
Interest Payable, Current
Interest payable
Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Before Tax
Other comprehensive income loss cash flow hedge gain loss before reclassification before tax
(Loss)/gain recognized in OCI (effective element)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest, Total
Comprehensive income attributable to non-controlling interests
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest
Total costs of providing services
Costs and Expenses
Finite-Lived Intangible Assets by Major Class
Finite-Lived Intangible Assets by Major Class [Axis]
Mergers, Acquisitions and Dispositions Disclosures [Text Block]
Acquisitions
Schedule of Current and Long-term Debt
Schedule of Debt [Table Text Block]
Payment, Tax Withholding, Share-Based Payment Arrangement
Cash paid for employee taxes on withholding shares
Cash paid for employee taxes on withholding shares
Equity Based Payment [Member]
Equity based payment.
Equity Based Payment
Revenue
Revenue from Contract with Customer [Text Block]
Business Combination [Table]
Entity Registrant Name
Entity Registrant Name
Entity Registrant Name
Debt
Debt Disclosure [Text Block]
Finite-Lived Intangible Asset, Expected Amortization, Year Two
2028
Other Nonoperating Income (Expense)
Other income/(loss), net
Other income/(loss), net
Other income/(loss), net
Accumulated Other Comprehensive Income Loss [Table]
Accumulated Other Comprehensive Income (Loss) [Table]
Balance Sheet Date
Balance Sheet Date [Axis]
Balance sheet date.
Other Comprehensive Income Loss Net Of Tax Including Portion Attributable To Nonredeemable Noncontrolling Interest
Other comprehensive income (loss), net of tax including portion attributable to nonredeemable noncontrolling interest.
Other comprehensive income (loss)
Effect on Future Earnings, Amount
Annual cost savings of program
Schedule of Other Nonoperating Income (Expense) [Table Text Block]
Schedule of Other Nonoperating Income/(Loss)
Finite-Lived Intangible Asset, Expected Amortization, Year Three
2029
Income Tax Expense (Benefit), Total
Provision for income taxes
Provision for income taxes
Income Tax Expense (Benefit)
Measurement Frequency
Measurement Frequency [Axis]
December Thirty One Two Thousand And Twenty Four [Member]
December thirty one two thousand and twenty four.
Dec 31, 2024 [Member]
Additions to fixed assets and software
Payments to Acquire Productive Assets
Payments to Acquire Productive Assets, Total
Business Combination, Contingent Consideration, Type [Axis]
Costs of providing services
Costs and Expenses [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Fair value significant transfers to or from Level 3
Fair Value Level Three Transfers Amount
Fair value level three transfers amount.
Percentage of ownership by non-controlling owner
Subsidiary, Ownership Percentage, Noncontrolling Owner
Entity Common Stock, Shares Outstanding
Entity Common Stock, Shares Outstanding
Liability Class
Liability Class [Axis]
Other Income and Other Expense Disclosure [Text Block]
Other Income/(Loss), Net
Foreign Countries [Member]
Total Foreign Countries [Member]
Foreign Countries Member
Accumulated Other Comprehensive Income (Loss), Net of Tax, Total
Accumulated other comprehensive loss, net of tax
Accumulated Other Comprehensive Income (Loss), Net of Tax
Consolidation Items
Consolidation Items [Axis]
Pending Acquisitions
Pending Acquisitions [Member]
Pending acquisitions.
Payments for Restructuring
Cash payments
Cash payments
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period
Number of shares issued
Number of shares, granted
TOTAL ASSETS
Assets
Revolving15 Billion Dollar Credit Facility [Member]
Revolving 15 Billion Dollar Credit Facility.
Revolving 1.5 Billion Dollar Credit Facility [Member]
Income Statement [Abstract]
Restructuring Cost [Table]
Fair Value of Financial Instruments
Fair Value of Financial Instruments, Policy [Policy Text Block]
Amortization of net loss
Defined Benefit Plan, Amortization of Gain (Loss)
Amortization of net loss
Technology modernization.
Technology modernization [Member]
Technology Modernization [Member]
Al-Futtaim Willis [Member]
Al-futtaim willis member.
Al-Futtaim Willis
Time Based Shares [Member]
Time-based shares.
Time-Based Award [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period
Vested (shares)
Business Combination [Abstract]
Accounts payable, accrued liabilities and deferred revenue
Accounts Payable, Other, Current
Diluted earnings per share
Diluted earnings per share
Earnings Per Share, Diluted
Schedule of Segment Reporting Information, by Segment
Schedule of Segment Reporting Information, by Segment [Table Text Block]
Operating Segments [Member]
Operating Segments [Member]
Restricted Stock Awards (RSAs) [Member]
Restricted stock awards (RSAs).
Restricted Stock Awards [Member]
Dividends, Common Stock, Total
Dividends declared
Dividends, Common Stock
City Area Code
City Area Code
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease)
Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Period Increase (Decrease), Total
Net total number of shares
Up Front [Member]
Up front.
Up-Front
Finite-lived Intangible Assets [Roll Forward]
Finite-Lived Intangible Assets [Roll Forward]
Debt Instrument, Face Amount
Debt instrument, face amount
Maximum borrowing capacity
Line of Credit Facility, Maximum Borrowing Capacity
Business Combination [Line Items]
International [Member]
International [Member]
International.
Schedule Of Defined Benefit Plans Disclosures [Table]
Defined Benefit Plan [Table]
Other Intangible Assets [Member]
Other [Member]
Counterparty Name
Counterparty Name [Domain]
Variable lease cost
Variable Lease, Cost
Transformation program.
Transformation Program [Member]
Transformation Program [Member]
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]
Segment Reporting Information [Line Items]
Segment Reporting Information [Line Items]
Disposal Group Name
Disposal Group Name [Axis]
Compensation and Retirement Disclosure [Line Items]
Compensation And Retirement Disclosure [Line Items]
Compensation and retirement disclosure.
Total lease cost, net
Lease, Cost
Lease cost
Leases
Lessee Operating And Finance Lease Disclosure [Text Block]
The entire disclosure for operating lease and finance lease by the lessee.
December thirty one two thousand and twenty three.
December Thirty One Two Thousand And Twenty Three [Member]
Dec 31, 2023 [Member]
Acquisiiton , equity payment
Business Combination, Consideration Transferred, Equity Interest
5.050% senior notes due 2048 [Member]
Senior Notes Due20480505 [Member]
Senior notes due 2048, 0505.
Derivative Liability, Current
Derivatives
Property, Plant and Equipment, Net, Ending Balance
Property, Plant and Equipment, Net, Beginning Balance
Property, Plant and Equipment, Net, Total
Fixed assets, net
Property, Plant and Equipment, Net
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Beginning Balance
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Ending Balance
Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation
Total cash, cash equivalents and restricted cash
Total cash, cash equivalents and restricted cash
Income from operations
Operating Income (Loss)
INCOME FROM OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES
Operating income
Foreign exchange
Goodwill, Foreign Currency Translation, Gain (Loss)
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block]
Revenue and Tangible Long-lived Assets by Geographical Areas
Ordinary shares, $0.000304635 nominal value [Member]
Ordinary Share One [Member]
Ordinary share one.
Derivative Instruments, Gain (Loss) Reclassification from Accumulated OCI to Income, Estimated Net Amount to be Transferred
Gains/losses on derivatives to be reclassified within the next twelve months
Gains on derivatives to be reclassified within the next twelve months
Retained earnings [Member]
Retained Earnings [Member]
Entity Address, Country
Entity Address, Country
Business Combination, Contingent Consideration, Type [Domain]
Cash and Cash Equivalents [Axis]
Total non-current assets
Assets, Noncurrent
Share-based Payment Arrangement, Noncash Expense, Total
Share-based compensation
Share-Based Payment Arrangement, Noncash Expense
Salaries And Benefits [Member]
Salaries and benefits.
Salaries and Benefits [Member]
Total non-current liabilities
Liabilities, Noncurrent
Long-term lease liabilities
Operating Lease, Liability, Noncurrent
Level 1 [Member]
Fair Value, Inputs, Level 1 [Member]
Cash Provided by (Used in) Financing Activity, Including Discontinued Operation
Net cash (used in)/from financing activities
Lease, Cost [Table Text Block]
Schedule of Amount Recorded in Consolidated Statements of Comprehensive Income
Developed Software [Member]
Developed Technology Rights [Member]
Provisions for Liabilities
Provisions For Liabilities Table [Text Block]
Provisions for liabilities.
Schedule of Prepaid and Other Current Assets
Schedule of Other Current Assets [Table Text Block]
Derivative Contract
Derivative Contract [Domain]
Schedule Of Goodwill [Table]
Goodwill [Table]
Business Combination, Recognized Asset Acquired, Receivable, Current
Accounts receivable, net
Foreign exchange
Finite-Lived Intangible Assets, Foreign Currency Translation Gain (Loss)
Longest outstanding maturity
Derivative, Remaining Maturity
Corporate Debt Securities [Member]
Corporate Debt Securities [Member]
Entity Interactive Data Current
Entity Interactive Data Current
Income Statement Location
Statement of Income Location, Balance [Domain]
Fair Value Measurement
Fair Value Measurement [Domain]
Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract]
CASH FLOWS USED IN OPERATING ACTIVITIES
Unbilled Receivable, Current
Unbilled Receivables, Current
Unbilled receivables
Net carrying amount
Net carrying amount
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings
Realized and unrealized losses
Realized and unrealized losses
Dividends declared per share
Common Stock, Dividends, Per Share, Declared
Entity Tax Identification Number
Entity Tax Identification Number
EQUITY
Equity, Including Portion Attributable to Noncontrolling Interest [Abstract]
Long-Term Debt, Type [Axis]
Risk and Broking.
Risk and Broking [Member]
R&B [Member]
R&B [Member]
Income from Operations Before Income Loss from Equity Method Investments
Income from operations before income loss from equity method investments.
INCOME FROM OPERATIONS BEFORE INTEREST IN EARNINGS OF ASSOCIATES
Effect of exchange rate changes on cash, cash equivalents and restricted cash
Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation
Miller [Member]
Miller [Member]
Miller.
Accrued Sales Commission, Current
Third-party commissions
Local Phone Number
Local Phone Number
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)
Net periodic benefit cost/(income)
Pension settlements
Total other current liabilities
Other current liabilities
Other Liabilities, Current
Long-Lived Assets
Long-Lived Assets
Accounting Policies [Abstract]
Insurance Premium
Market insurance premium.
Premiums to the insurance market
Contract with Customer, Performance Obligation Satisfied in Previous Period
Contract with Customer, Performance Obligation Satisfied in Previous Period
Disaggregation Of Revenue [Line Items]
Disaggregation of Revenue [Line Items]
Other Sundry Liabilities, Current
Other current liabilities
Revenue from Contract with Customer, Excluding Assessed Tax, Total
Revenue from Contract with Customer, Excluding Assessed Tax
Revenue from Contract with Customer, Excluding Assessed Tax
Class of Stock
Class of Stock [Domain]
Salaries and benefits
Labor and Related Expense
Deferred Revenue and Accrued Expenses
Schedule of Accounts Payable and Accrued Liabilities [Table Text Block]
Health, Wealth and Career
Health, Wealth and Career [Member]
HWC [Member]
HWC [Member]
Accumulated impairment losses, beginning balance
Accumulated impairment losses, ending balance
Goodwill, Impaired, Accumulated Impairment Loss
Entity Emerging Growth Company
Entity Emerging Growth Company
Net assets acquired
Business Combination, Recognized Asset Acquired to Liability Assumed, Excess (Less), and Goodwill