XML 91 R84.htm IDEA: XBRL DOCUMENT
v3.25.3

Supplementary Information for Certain Balance Sheet Accounts - Provision For Liabilities (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Organization, Consolidation and Presentation of Financial Statements [Abstract] |  |
Claims, lawsuits and other proceedings | $ 307 | $ 284
Other provisions | 62 | 57
Total provision for liabilities | $ 369 | $ 341

X
- Definition Carrying amount of estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid after one year or beyond the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(25)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_LitigationReserveNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of expenses incurred but not yet paid classified as other, due after one year or the normal operating cycle, if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(24)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 + Details
Name: | us-gaap_OtherAccruedLiabilitiesNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Provision for liabilities non current. + References No definition available. + Details
Name: | wtw_ProvisionForLiabilitiesNonCurrent
Namespace Prefix: | wtw_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant