{"cik":1140536,"taxonomy":"us-gaap","tag":"AllocatedShareBasedCompensationExpense","label":"Share-based Payment Arrangement, Expense","description":"Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.","entityName":"WILLIS TOWERS WATSON PLC","units":{"USD":[{"start":"2008-12-31","end":"2009-12-31","val":39000000,"accn":"0000950123-12-004309","fy":2011,"fp":"FY","form":"10-K","filed":"2012-02-29","frame":"CY2009"},{"start":"2009-12-31","end":"2010-12-31","val":47000000,"accn":"0000950123-12-004309","fy":2011,"fp":"FY","form":"10-K","filed":"2012-02-29","frame":"CY2010"},{"start":"2010-12-31","end":"2011-12-31","val":41000000,"accn":"0000950123-12-004309","fy":2011,"fp":"FY","form":"10-K","filed":"2012-02-29","frame":"CY2011"},{"start":"2014-01-01","end":"2014-12-31","val":52000000,"accn":"0001140536-17-000008","fy":2016,"fp":"FY","form":"10-K","filed":"2017-03-01","frame":"CY2014"},{"start":"2015-01-01","end":"2015-12-31","val":64000000,"accn":"0001140536-17-000008","fy":2016,"fp":"FY","form":"10-K","filed":"2017-03-01"},{"start":"2015-01-01","end":"2015-12-31","val":64000000,"accn":"0001140536-18-000008","fy":2017,"fp":"FY","form":"10-K","filed":"2018-02-28"},{"start":"2015-01-01","end":"2015-12-31","val":64000000,"accn":"0001140536-18-000016","fy":2017,"fp":"FY","form":"10-K","filed":"2018-06-06","frame":"CY2015"},{"start":"2016-01-01","end":"2016-12-31","val":123000000,"accn":"0001140536-17-000008","fy":2016,"fp":"FY","form":"10-K","filed":"2017-03-01"},{"start":"2016-01-01","end":"2016-12-31","val":123000000,"accn":"0001140536-18-000008","fy":2017,"fp":"FY","form":"10-K","filed":"2018-02-28"},{"start":"2016-01-01","end":"2016-12-31","val":123000000,"accn":"0001140536-18-000016","fy":2017,"fp":"FY","form":"10-K","filed":"2018-06-06"},{"start":"2016-01-01","end":"2016-12-31","val":123000000,"accn":"0001564590-19-004912","fy":2018,"fp":"FY","form":"10-K","filed":"2019-02-27","frame":"CY2016"},{"start":"2017-01-01","end":"2017-12-31","val":67000000,"accn":"0001140536-18-000008","fy":2017,"fp":"FY","form":"10-K","filed":"2018-02-28"},{"start":"2017-01-01","end":"2017-12-31","val":67000000,"accn":"0001140536-18-000016","fy":2017,"fp":"FY","form":"10-K","filed":"2018-06-06"},{"start":"2017-01-01","end":"2017-12-31","val":67000000,"accn":"0001564590-19-004912","fy":2018,"fp":"FY","form":"10-K","filed":"2019-02-27"},{"start":"2017-01-01","end":"2017-12-31","val":67000000,"accn":"0001564590-20-006736","fy":2019,"fp":"FY","form":"10-K","filed":"2020-02-26","frame":"CY2017"},{"start":"2018-01-01","end":"2018-12-31","val":50000000,"accn":"0001564590-19-004912","fy":2018,"fp":"FY","form":"10-K","filed":"2019-02-27"},{"start":"2018-01-01","end":"2018-12-31","val":50000000,"accn":"0001564590-20-006736","fy":2019,"fp":"FY","form":"10-K","filed":"2020-02-26"},{"start":"2018-01-01","end":"2018-12-31","val":50000000,"accn":"0001564590-21-007578","fy":2020,"fp":"FY","form":"10-K","filed":"2021-02-23","frame":"CY2018"},{"start":"2019-01-01","end":"2019-12-31","val":74000000,"accn":"0001564590-20-006736","fy":2019,"fp":"FY","form":"10-K","filed":"2020-02-26"},{"start":"2019-01-01","end":"2019-12-31","val":74000000,"accn":"0001564590-21-007578","fy":2020,"fp":"FY","form":"10-K","filed":"2021-02-23"},{"start":"2019-01-01","end":"2019-12-31","val":74000000,"accn":"0000950170-22-001932","fy":2021,"fp":"FY","form":"10-K","filed":"2022-02-24","frame":"CY2019"},{"start":"2020-01-01","end":"2020-12-31","val":90000000,"accn":"0001564590-21-007578","fy":2020,"fp":"FY","form":"10-K","filed":"2021-02-23"},{"start":"2020-01-01","end":"2020-12-31","val":90000000,"accn":"0000950170-22-001932","fy":2021,"fp":"FY","form":"10-K","filed":"2022-02-24"},{"start":"2020-01-01","end":"2020-12-31","val":90000000,"accn":"0000950170-23-004303","fy":2021,"fp":"FY","form":"10-K","filed":"2023-02-24","frame":"CY2020"},{"start":"2021-01-01","end":"2021-12-31","val":101000000,"accn":"0000950170-22-001932","fy":2021,"fp":"FY","form":"10-K","filed":"2022-02-24"},{"start":"2021-01-01","end":"2021-12-31","val":101000000,"accn":"0000950170-23-004303","fy":2021,"fp":"FY","form":"10-K","filed":"2023-02-24"},{"start":"2021-01-01","end":"2021-12-31","val":101000000,"accn":"0000950170-24-018575","fy":2021,"fp":"FY","form":"10-K","filed":"2024-02-22","frame":"CY2021"},{"start":"2022-01-01","end":"2022-12-31","val":99000000,"accn":"0000950170-23-004303","fy":2021,"fp":"FY","form":"10-K","filed":"2023-02-24"},{"start":"2022-01-01","end":"2022-12-31","val":99000000,"accn":"0000950170-24-018575","fy":2021,"fp":"FY","form":"10-K","filed":"2024-02-22"},{"start":"2022-01-01","end":"2022-12-31","val":99000000,"accn":"0000950170-25-026278","fy":2024,"fp":"FY","form":"10-K","filed":"2025-02-25","frame":"CY2022"},{"start":"2023-01-01","end":"2023-12-31","val":125000000,"accn":"0000950170-24-018575","fy":2021,"fp":"FY","form":"10-K","filed":"2024-02-22"},{"start":"2023-01-01","end":"2023-12-31","val":125000000,"accn":"0000950170-25-026278","fy":2024,"fp":"FY","form":"10-K","filed":"2025-02-25"},{"start":"2023-01-01","end":"2023-12-31","val":125000000,"accn":"0001193125-26-069307","fy":2025,"fp":"FY","form":"10-K","filed":"2026-02-25","frame":"CY2023"},{"start":"2024-01-01","end":"2024-12-31","val":121000000,"accn":"0000950170-25-026278","fy":2024,"fp":"FY","form":"10-K","filed":"2025-02-25"},{"start":"2024-01-01","end":"2024-12-31","val":121000000,"accn":"0001193125-26-069307","fy":2025,"fp":"FY","form":"10-K","filed":"2026-02-25","frame":"CY2024"},{"start":"2025-01-01","end":"2025-03-31","val":37000000,"accn":"0001193125-26-195310","fy":2026,"fp":"Q1","form":"10-Q","filed":"2026-04-30","frame":"CY2025Q1"},{"start":"2025-01-01","end":"2025-06-30","val":68000000,"accn":"0001193125-26-325374","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-07-30"},{"start":"2025-04-01","end":"2025-06-30","val":31000000,"accn":"0001193125-26-325374","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-07-30","frame":"CY2025Q2"},{"start":"2025-01-01","end":"2025-12-31","val":153000000,"accn":"0001193125-26-069307","fy":2025,"fp":"FY","form":"10-K","filed":"2026-02-25","frame":"CY2025"},{"start":"2026-01-01","end":"2026-03-31","val":42000000,"accn":"0001193125-26-195310","fy":2026,"fp":"Q1","form":"10-Q","filed":"2026-04-30","frame":"CY2026Q1"},{"start":"2026-01-01","end":"2026-06-30","val":109000000,"accn":"0001193125-26-325374","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-07-30"},{"start":"2026-04-01","end":"2026-06-30","val":67000000,"accn":"0001193125-26-325374","fy":2026,"fp":"Q2","form":"10-Q","filed":"2026-07-30","frame":"CY2026Q2"}]}}