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Restructuring Costs (Restructuring Activities) (Details) - USD ($) $ in Millions | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2020 | Dec. 31, 2019
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | $ 102 | $ 112
Amounts Accrued | 43 | 112
Cash Paid | (85) | (112)
Other | (2) | (10)
Liability at end of period | 58 | 102
Severance |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 51 | 73
Amounts Accrued | 15 | 73
Cash Paid | (51) | (91)
Other | 0 | (4)
Liability at end of period | 15 | 51
Future rent under non-cancelable leases and other costs |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 51 | 39
Amounts Accrued | 28 | 39
Cash Paid | (34) | (21)
Other | (2) | (6)
Liability at end of period | 43 | 51
Jardine Lloyd Thompson Group plc |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 47 | 0
Amounts Accrued | 181 | 335
Cash Paid | (169) | (265)
Non-cash charges | (31) | (23)
Liability at end of period | 28 | 47
Jardine Lloyd Thompson Group plc | Severance |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 42 | 0
Amounts Accrued | 38 | 154
Cash Paid | (70) | (112)
Non-cash charges | 0 | 0
Liability at end of period | 10 | 42
Jardine Lloyd Thompson Group plc | Real estate related costs |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 5 | 0
Amounts Accrued | 42 | 38
Cash Paid | (15) | (14)
Non-cash charges | (26) | (19)
Liability at end of period | 6 | 5
Jardine Lloyd Thompson Group plc | Information Technology |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 0 | 0
Amounts Accrued | 45 | 45
Cash Paid | (40) | (45)
Non-cash charges | (5) | 0
Liability at end of period | 0 | 0
Jardine Lloyd Thompson Group plc | Consulting and other outside services |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 0 | 0
Amounts Accrued | 56 | 98
Cash Paid | (44) | (94)
Non-cash charges | 0 | (4)
Liability at end of period | $ 12 | $ 0

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