Fair Value Measurements - Fair Value Measurement (Details) - USD ($) $ in Millions	Mar. 31, 2022	Dec. 31, 2021
Assets:
Derivatives	$ 175	$ 149
Assets held in separate accounts	89,965	96,964
Liabilities:
Derivatives	210	144
U.S. Treasuries
Assets:
Fixed maturities, including securities pledged	651	691
US Treasury and Government
Assets:
Fixed maturities, including securities pledged	19	20
State, municipalities and political subdivisions
Assets:
Fixed maturities, including securities pledged	721	803
U.S. corporate public securities
Assets:
Fixed maturities, including securities pledged	7,409	8,269
U.S. corporate private securities
Assets:
Fixed maturities, including securities pledged	3,674	3,939
Foreign corporate public securities and foreign governments
Assets:
Fixed maturities, including securities pledged	2,320	2,591
Foreign corporate private securities
Assets:
Fixed maturities, including securities pledged	2,592	2,703
Residential mortgage-backed
Assets:
Fixed maturities, including securities pledged	3,065	3,164
Commercial mortgage-backed
Assets:
Fixed maturities, including securities pledged	2,879	2,881
Other asset-backed securities
Assets:
Fixed maturities, including securities pledged	1,273	1,351
Assets measured on recurring basis
Assets:
Fixed maturities, including securities pledged	24,603	26,412
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreement	967	1,244
Assets held in separate accounts	89,965	96,964
Total assets, fair value	$ 115,847	$ 124,910
Percentage of Level to total assets	100.00%	100.00%
Liabilities:
Total liabilities, fair value	$ 234	$ 173
Assets measured on recurring basis | FIA
Liabilities:
Product guarantees	9	9
Assets measured on recurring basis | Stabilizer and MCGs
Liabilities:
Product guarantees	15	20
Assets measured on recurring basis | Interest rate contracts
Assets:
Derivatives	158	135
Liabilities:
Derivatives	198	129
Assets measured on recurring basis | Foreign exchange contracts
Assets:
Derivatives	17	14
Liabilities:
Derivatives	11	15
Assets measured on recurring basis | Credit contracts
Liabilities:
Derivatives	1
Assets measured on recurring basis | U.S. Treasuries
Assets:
Fixed maturities, including securities pledged	651	691
Assets measured on recurring basis | US Treasury and Government
Assets:
Fixed maturities, including securities pledged	19	20
Assets measured on recurring basis | State, municipalities and political subdivisions
Assets:
Fixed maturities, including securities pledged	721	803
Assets measured on recurring basis | U.S. corporate public securities
Assets:
Fixed maturities, including securities pledged	7,409	8,269
Assets measured on recurring basis | U.S. corporate private securities
Assets:
Fixed maturities, including securities pledged	3,674	3,939
Assets measured on recurring basis | Foreign corporate public securities and foreign governments
Assets:
Fixed maturities, including securities pledged	2,320	2,591
Assets measured on recurring basis | Foreign corporate private securities
Assets:
Fixed maturities, including securities pledged	2,592	2,703
Assets measured on recurring basis | Residential mortgage-backed
Assets:
Fixed maturities, including securities pledged	3,065	3,164
Assets measured on recurring basis | Commercial mortgage-backed
Assets:
Fixed maturities, including securities pledged	2,879	2,881
Assets measured on recurring basis | Other asset-backed securities
Assets:
Fixed maturities, including securities pledged	1,273	1,351
Assets measured on recurring basis | Equity securities
Liabilities:
Equity Securities, FV-NI	137	141
Assets measured on recurring basis | Level 1
Assets:
Fixed maturities, including securities pledged	482	510
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreement	960	1,244
Assets held in separate accounts	84,193	91,474
Total assets, fair value	$ 85,650	$ 93,255
Percentage of Level to total assets	74.00%	74.00%
Liabilities:
Total liabilities, fair value	$ 0	$ 0
Assets measured on recurring basis | Level 1 | FIA
Liabilities:
Product guarantees	0	0
Assets measured on recurring basis | Level 1 | Stabilizer and MCGs
Liabilities:
Product guarantees	0	0
Assets measured on recurring basis | Level 1 | Interest rate contracts
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Assets measured on recurring basis | Level 1 | Foreign exchange contracts
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Assets measured on recurring basis | Level 1 | Credit contracts
Liabilities:
Derivatives	0
Assets measured on recurring basis | Level 1 | U.S. Treasuries
Assets:
Fixed maturities, including securities pledged	482	510
Assets measured on recurring basis | Level 1 | US Treasury and Government
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | State, municipalities and political subdivisions
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | U.S. corporate public securities
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | U.S. corporate private securities
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Foreign corporate public securities and foreign governments
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Foreign corporate private securities
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Residential mortgage-backed
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Commercial mortgage-backed
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Other asset-backed securities
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 1 | Equity securities
Liabilities:
Equity Securities, FV-NI	15	27
Assets measured on recurring basis | Level 2
Assets:
Fixed maturities, including securities pledged	22,196	24,179
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreement	0	0
Assets held in separate accounts	5,438	5,174
Total assets, fair value	$ 27,814	$ 29,502
Percentage of Level to total assets	24.00%	24.00%
Liabilities:
Total liabilities, fair value	$ 210	$ 144
Assets measured on recurring basis | Level 2 | FIA
Liabilities:
Product guarantees	0	0
Assets measured on recurring basis | Level 2 | Stabilizer and MCGs
Liabilities:
Product guarantees	0	0
Assets measured on recurring basis | Level 2 | Interest rate contracts
Assets:
Derivatives	158	135
Liabilities:
Derivatives	198	129
Assets measured on recurring basis | Level 2 | Foreign exchange contracts
Assets:
Derivatives	17	14
Liabilities:
Derivatives	11	15
Assets measured on recurring basis | Level 2 | Credit contracts
Liabilities:
Derivatives	1
Assets measured on recurring basis | Level 2 | U.S. Treasuries
Assets:
Fixed maturities, including securities pledged	169	181
Assets measured on recurring basis | Level 2 | US Treasury and Government
Assets:
Fixed maturities, including securities pledged	19	20
Assets measured on recurring basis | Level 2 | State, municipalities and political subdivisions
Assets:
Fixed maturities, including securities pledged	721	803
Assets measured on recurring basis | Level 2 | U.S. corporate public securities
Assets:
Fixed maturities, including securities pledged	7,362	8,264
Assets measured on recurring basis | Level 2 | U.S. corporate private securities
Assets:
Fixed maturities, including securities pledged	2,250	2,560
Assets measured on recurring basis | Level 2 | Foreign corporate public securities and foreign governments
Assets:
Fixed maturities, including securities pledged	2,317	2,591
Assets measured on recurring basis | Level 2 | Foreign corporate private securities
Assets:
Fixed maturities, including securities pledged	2,214	2,431
Assets measured on recurring basis | Level 2 | Residential mortgage-backed
Assets:
Fixed maturities, including securities pledged	3,028	3,130
Assets measured on recurring basis | Level 2 | Commercial mortgage-backed
Assets:
Fixed maturities, including securities pledged	2,879	2,881
Assets measured on recurring basis | Level 2 | Other asset-backed securities
Assets:
Fixed maturities, including securities pledged	1,237	1,318
Assets measured on recurring basis | Level 2 | Equity securities
Liabilities:
Equity Securities, FV-NI	5	0
Assets measured on recurring basis | Level 3
Assets:
Fixed maturities, including securities pledged	1,925	1,723
Cash and cash equivalents, short-term investments and short-term investments under securities loan agreement	7	0
Assets held in separate accounts	334	316
Total assets, fair value	$ 2,383	$ 2,153
Percentage of Level to total assets	2.00%	2.00%
Liabilities:
Total liabilities, fair value	$ 24	$ 29
Assets measured on recurring basis | Level 3 | FIA
Liabilities:
Product guarantees	9	9
Assets measured on recurring basis | Level 3 | Stabilizer and MCGs
Liabilities:
Product guarantees	15	20
Assets measured on recurring basis | Level 3 | Interest rate contracts
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Assets measured on recurring basis | Level 3 | Foreign exchange contracts
Assets:
Derivatives	0	0
Liabilities:
Derivatives	0	0
Assets measured on recurring basis | Level 3 | Credit contracts
Liabilities:
Derivatives	0
Assets measured on recurring basis | Level 3 | U.S. Treasuries
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 3 | US Treasury and Government
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 3 | State, municipalities and political subdivisions
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 3 | U.S. corporate public securities
Assets:
Fixed maturities, including securities pledged	47	5
Assets measured on recurring basis | Level 3 | U.S. corporate private securities
Assets:
Fixed maturities, including securities pledged	1,424	1,379
Assets measured on recurring basis | Level 3 | Foreign corporate public securities and foreign governments
Assets:
Fixed maturities, including securities pledged	3	0
Assets measured on recurring basis | Level 3 | Foreign corporate private securities
Assets:
Fixed maturities, including securities pledged	378	272
Assets measured on recurring basis | Level 3 | Residential mortgage-backed
Assets:
Fixed maturities, including securities pledged	37	34
Assets measured on recurring basis | Level 3 | Commercial mortgage-backed
Assets:
Fixed maturities, including securities pledged	0	0
Assets measured on recurring basis | Level 3 | Other asset-backed securities
Assets:
Fixed maturities, including securities pledged	36	33
Assets measured on recurring basis | Level 3 | Equity securities
Liabilities:
Equity Securities, FV-NI	$ 117	$ 114