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Subsequent Event - Detail of fixed maturity investments held by subsidiaries to be disposed (Details) - USD ($) $ in Millions | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | $ 43,207 | $ 46,505
Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 34,123 |
U.S. government agency |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 242 | 209
U.S. government agency | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 44 |
State and municipal |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 5,733 | 6,963
State and municipal | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 3,421 |
Debt Security, Government, Non-US [Member] |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 211 | 172
Debt Security, Government, Non-US [Member] | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 35 |
Residential MBS |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 3,055 | 3,160
Residential MBS | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 2,140 |
Commercial MBS |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 790 | 927
Commercial MBS | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 698 |
Collateralized loan obligations | Managed by third parties |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 4,553 | 4,280
Collateralized loan obligations | Managed by third parties | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 3,491 |
Other asset-backed securities |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 7,223 | 7,128
Other asset-backed securities | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 5,176 |
Corporate and other |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 21,400 | 23,666
Corporate and other | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 19,118 |
Total fixed maturities |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | 43,207 | $ 46,505
Total fixed maturities | Great American Life Insurance Company |  |
Subsequent Event [Line Items] |  |
Available for sale (AFS) fixed maturities | $ 34,123 |

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- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563 + Details
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- Definition Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event. + References No definition available. + Details
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