Investments (excluding Consolidated Investment Entities) - Fixed Maturities (Details) - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2021	Dec. 31, 2020
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		$ 30,656	$ 37,531
Securities pledged, Amortized Cost		1,091	355
Fixed maturities, including securities pledged		$ 33,699	43,569
Fixed maturities, single issuers in excess of total equity		no
Commercial mortgage loans
Available-for-sale Securities, Including Securities Pledged [Line Items]
Post-modification carrying value		$ 5	63
U.S. Treasuries
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		764	1,033
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		239	438
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		0	0
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		1,003	1,471
OTTI	$ 0	0
U.S. Government agencies and authorities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		69	74
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		12	28
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		0	0
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		81	102
OTTI	0	0
State, municipalities, and political subdivisions
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		1,000	1,166
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		112	180
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		1	0
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		1,111	1,346
OTTI	0	0
U.S. corporate public securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		10,402	13,366
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		1,580	3,028
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		41	7
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		11,941	16,387
OTTI	0	0
U.S. corporate private securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		4,889	5,653
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		459	828
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		23	35
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		5,325	6,446
OTTI	0	0
Foreign corporate public securities and foreign governments
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		3,373	4,023
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		368	714
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		18	1
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		3,723	4,736
OTTI	0	0
Foreign corporate private securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		3,320	4,220
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		238	470
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		1	29
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		3,501	4,646
OTTI	15	56
Residential mortgage-backed securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		4,183	5,370
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		139	255
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		31	17
Embedded Derivatives		12	20
Fixed maturities, including securities pledged		4,302	5,626
OTTI	2	1
Commercial mortgage-backed securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		4,032	3,882
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		173	290
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		22	40
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		4,183	4,131
OTTI	1	0
Other asset-backed securities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		2,069	2,110
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		25	46
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		12	10
Embedded Derivatives		0	0
Fixed maturities, including securities pledged		2,081	2,138
OTTI	8	1
Fixed maturities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Fixed maturities, including securities pledged, Amortized Cost Basis		34,101	40,897
Total fixed maturities, less securities pledged, Amortized Cost		33,010	40,542
Fixed maturities, including securities pledged, Gross Unrealized Capital Gains		3,345	6,277
Total fixed maturities, less securities pledged, Gross Unrealized Capital Gains		3,238	6,182
Fixed maturities, including securities pledged,Gross Unrealized Capital Losses		149	139
Total fixed maturities, less securities pledged, Gross Unrealized Capital Losses		149	138
Embedded Derivatives		12	20
Fixed maturities, including securities pledged		37,251	47,029
Total fixed maturities, less securities pledged, Fair Value		36,053	46,580
OTTI	26	58
Collateral pledged
Available-for-sale Securities, Including Securities Pledged [Line Items]
Securities pledged		1,198	449
Collateral pledged | Fixed maturities
Available-for-sale Securities, Including Securities Pledged [Line Items]
Securities pledged, Amortized Cost		1,091	355
Securities pledged, Gross Unrealized Capital Gains		107	95
Securities pledged, Gross Unrealized Capital Losses		0	1
Embedded Derivatives		0	0
Securities pledged		1,198	$ 449
OTTI	$ 0	$ 0