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Restructuring Costs (Restructuring Activities) (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | $ 81 | $ 102
Amounts Accrued | 11 | 89
Cash Paid | (28) | (100)
Non-Cash/Other | 0 | (10)
Liability at end of period | 64 | 81
Severance |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 36 | 51
Amounts Accrued | 5 | 39
Cash Paid | (20) | (54)
Non-Cash/Other | 0 | 0
Liability at end of period | 21 | 36
Future rent under non-cancelable leases and other costs |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 45 | 51
Amounts Accrued | 6 | 50
Cash Paid | (8) | (46)
Non-Cash/Other | 0 | (10)
Liability at end of period | 43 | 45
Jardine Lloyd Thompson Group plc |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 25 | 47
Amounts Accrued | 23 | 251
Cash Paid | (26) | (226)
Non-cash charges | (4) | (47)
Liability at end of period | 18 | 25
Jardine Lloyd Thompson Group plc | Severance |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 16 | 42
Amounts Accrued | 2 | 43
Cash Paid | (10) | (69)
Non-cash charges | 0 | 0
Liability at end of period | 8 | 16
Jardine Lloyd Thompson Group plc | Real estate related costs |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 7 | 5
Amounts Accrued | 6 | 69
Cash Paid | (2) | (25)
Non-cash charges | (4) | (42)
Liability at end of period | 7 | 7
Jardine Lloyd Thompson Group plc | Information Technology |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 2 | 0
Amounts Accrued | 7 | 62
Cash Paid | (7) | (55)
Non-cash charges | 0 | (5)
Liability at end of period | 2 | 2
Jardine Lloyd Thompson Group plc | Consulting and other outside services |  |
Restructuring Reserve [Roll Forward] |  |
Liability at beginning of period | 0 | 0
Amounts Accrued | 8 | 77
Cash Paid | (7) | (77)
Non-cash charges | 0 | 0
Liability at end of period | $ 1 | $ 0

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- Definition Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585 + Details
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- Definition Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747 + Details
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