Fair Value of Financial Instruments - Carrying Amounts of Assets and Liabilities at Estimated Fair Value Measured on a Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2022	Dec. 31, 2021
Assets
Fixed maturity securities available for sale	$ 30,432	$ 31,990
Derivative investments	145	816
Total financial assets at fair value	6,229	5,600
Level 1
Assets
Cash and cash equivalents	2,426	4,360
Short term investments	1,814	168
Derivative investments	0	0
Total financial assets at fair value	6,040	6,803
Derivatives:
Total financial liabilities at fair value	0	0
Level 2
Assets
Cash and cash equivalents	0	0
Short term investments	774	2
Derivative investments	145	816
Total financial assets at fair value	25,449	27,948
Derivatives:
Total financial liabilities at fair value	0	73
Level 3
Assets
Cash and cash equivalents	0	0
Short term investments	0	321
Derivative investments	0	0
Total financial assets at fair value	6,229	5,600
Derivatives:
Total financial liabilities at fair value	2,941	3,883
Fair Value
Assets
Cash and cash equivalents	2,426	4,360
Short term investments	2,588	491
Derivative investments	145	816
Total financial assets at fair value	37,718	40,351
Derivatives:
Total financial liabilities at fair value	2,941	3,956
Carrying Value
Assets
Cash and cash equivalents	2,426	4,360
Short term investments	2,588	491
Derivative investments	145	816
Total financial assets at fair value	37,718	40,351
Derivatives:
Total financial liabilities at fair value	2,941	3,956
Reinsurance related embedded derivative, included in other assets \| Level 1
Assets
Derivative investments	0
Reinsurance related embedded derivative, included in other assets \| Level 2
Assets
Derivative investments	191
Reinsurance related embedded derivative, included in other assets \| Level 3
Assets
Derivative investments	0
Reinsurance related embedded derivative, included in other assets \| Fair Value
Assets
Derivative investments	191
Reinsurance related embedded derivative, included in other assets \| Carrying Value
Assets
Derivative investments	191
FIA embedded derivatives, included in contractholder funds \| Level 1
Derivatives:
Derivative liability	0	0
FIA embedded derivatives, included in contractholder funds \| Level 2
Derivatives:
Derivative liability	0	0
FIA embedded derivatives, included in contractholder funds \| Level 3
Derivatives:
Derivative liability	2,941	3,883
FIA embedded derivatives, included in contractholder funds \| Fair Value
Derivatives:
Derivative liability	2,941	3,883
FIA embedded derivatives, included in contractholder funds \| Carrying Value
Derivatives:
Derivative liability	2,941	3,883
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities \| Level 1
Derivatives:
Derivative liability		0
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities \| Level 2
Derivatives:
Derivative liability		73
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities \| Level 3
Derivatives:
Derivative liability		0
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities \| Fair Value
Derivatives:
Derivative liability		73
Reinsurance related embedded derivatives, included in accounts payable and accrued liabilities \| Carrying Value
Derivatives:
Derivative liability		73
Asset-backed securities
Assets
Fixed maturity securities available for sale	9,448	8,695
Asset-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Asset-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	4,771	4,736
Asset-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	4,677	3,959
Asset-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	9,448	8,695
Asset-backed securities \| Carrying Value
Assets
Fixed maturity securities available for sale	9,448	8,695
Commercial mortgage-backed securities
Assets
Fixed maturity securities available for sale	3,053	2,979
Commercial mortgage-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Commercial mortgage-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	3,016	2,944
Commercial mortgage-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	37	35
Commercial mortgage-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	3,053	2,979
Commercial mortgage-backed securities \| Carrying Value
Assets
Fixed maturity securities available for sale	3,053	2,979
Corporates
Assets
Fixed maturity securities available for sale	14,184	16,494
Corporates \| Level 1
Assets
Fixed maturity securities available for sale	40	37
Corporates \| Level 2
Assets
Fixed maturity securities available for sale	12,770	15,322
Corporates \| Level 3
Assets
Fixed maturity securities available for sale	1,374	1,135
Corporates \| Fair Value
Assets
Fixed maturity securities available for sale	14,184	16,494
Corporates \| Carrying Value
Assets
Fixed maturity securities available for sale	14,184	16,494
Hybrids
Assets
Fixed maturity securities available for sale	769	912
Hybrids \| Level 1
Assets
Fixed maturity securities available for sale	118	132
Hybrids \| Level 2
Assets
Fixed maturity securities available for sale	651	780
Hybrids \| Level 3
Assets
Fixed maturity securities available for sale	0	0
Hybrids \| Fair Value
Assets
Fixed maturity securities available for sale	769	912
Hybrids \| Carrying Value
Assets
Fixed maturity securities available for sale	769	912
Municipals \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Municipals \| Level 2
Assets
Fixed maturity securities available for sale	1,278	1,458
Municipals \| Level 3
Assets
Fixed maturity securities available for sale	33	43
Municipals \| Fair Value
Assets
Fixed maturity securities available for sale	1,311	1,501
Municipals \| Carrying Value
Assets
Fixed maturity securities available for sale	1,311	1,501
Residential mortgage-backed securities
Assets
Fixed maturity securities available for sale	902	731
Residential mortgage-backed securities \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Residential mortgage-backed securities \| Level 2
Assets
Fixed maturity securities available for sale	893	731
Residential mortgage-backed securities \| Level 3
Assets
Fixed maturity securities available for sale	9	0
Residential mortgage-backed securities \| Fair Value
Assets
Fixed maturity securities available for sale	902	731
Residential mortgage-backed securities \| Carrying Value
Assets
Fixed maturity securities available for sale	902	731
U.S. Government
Assets
Fixed maturity securities available for sale	530	394
U.S. Government \| Level 1
Assets
Fixed maturity securities available for sale	530	394
U.S. Government \| Level 2
Assets
Fixed maturity securities available for sale	0	0
U.S. Government \| Level 3
Assets
Fixed maturity securities available for sale	0	0
U.S. Government \| Fair Value
Assets
Fixed maturity securities available for sale	530	394
U.S. Government \| Carrying Value
Assets
Fixed maturity securities available for sale	530	394
Foreign Governments
Assets
Fixed maturity securities available for sale	235	284
Foreign Governments \| Level 1
Assets
Fixed maturity securities available for sale	0	0
Foreign Governments \| Level 2
Assets
Fixed maturity securities available for sale	219	266
Foreign Governments \| Level 3
Assets
Fixed maturity securities available for sale	16	18
Foreign Governments \| Fair Value
Assets
Fixed maturity securities available for sale	235	284
Foreign Governments \| Carrying Value
Assets
Fixed maturity securities available for sale	235	284
Preferred securities
Assets
Equity and preferred securities	1,154	1,401
Preferred securities \| Level 1
Assets
Equity and preferred securities	411	506
Preferred securities \| Level 2
Assets
Equity and preferred securities	741	893
Preferred securities \| Level 3
Assets
Equity and preferred securities	1	2
Preferred securities \| Fair Value
Assets
Equity and preferred securities	1,153	1,401
Preferred securities \| Carrying Value
Assets
Equity and preferred securities	1,153	1,401
Equity securities \| Level 1
Assets
Equity and preferred securities	701	1,206
Equity securities \| Level 2
Assets
Equity and preferred securities	0	0
Equity securities \| Level 3
Assets
Equity and preferred securities	10	9
Equity securities \| Fair Value
Assets
Equity and preferred securities	711	1,215
Equity securities \| Carrying Value
Assets
Equity and preferred securities	711	1,215
Other long-term investments \| Level 1
Assets
Other long-term investments	0	0
Other long-term investments \| Level 2
Assets
Other long-term investments	0	0
Other long-term investments \| Level 3
Assets
Other long-term investments	72	78
Other long-term investments \| Fair Value
Assets
Other long-term investments	72	78
Other long-term investments \| Carrying Value
Assets
Other long-term investments	$ 72	$ 78

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