MRBs (Summary of Balances of Changes in Net MRB (Assets) Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2023	Dec. 31, 2022
Market Risk Benefit [Line Items]
Balance as of Beginning-of-year	$ (729)
Balance as of ending-of-year	(1,469)	$ (729)
Fixed Annuities [Member]
Market Risk Benefit [Line Items]
Balance as of Beginning-of-year	(45)	114
Balance as of beginning-of-year, before the effect of changes in non-performance risk	(5)	158
Attributed fees collected	9	32
Effect of changes in interest rates	31	(232)
Effect of changes in equity markets	(2)	12
Effect of changes in equity index volatility		14
In-force updates and other changes in MRBs	1	10
Effect of changes in future expected policyholder behavior		1
Balance as of end-of-year, before the effect of changes in non-performance risk	34	(5)
Effect of changes in non performance risk	(65)	(40)
Balance as of ending-of-year	(31)	(45)
Balance as of end-of-year, net of reinsurance	$ (31)	$ (45)
Weighted-average age of policyholder (years)	68 years	68 years
Market Risk Benefit, Net Amount at Risk	$ 192	$ 171
Retirement Plan Services Segment [Member]
Market Risk Benefit [Line Items]
Balance as of Beginning-of-year	(22)	(1)
Balance as of beginning-of-year, before the effect of changes in non-performance risk	(20)	12
Issuances		(3)
Attributed fees collected	2	6
Effect of changes in interest rates	5	(55)
Effect of changes in equity markets	(6)	18
Effect of changes in equity index volatility	(2)	(1)
In-force updates and other changes in MRBs		3
Balance as of end-of-year, before the effect of changes in non-performance risk	(21)	(20)
Effect of changes in non performance risk	(5)	(2)
Balance as of ending-of-year	(26)	(22)
Balance as of end-of-year, net of reinsurance	$ (26)	$ (22)
Weighted-average age of policyholder (years)	63 years	63 years
Market Risk Benefit, Net Amount at Risk	$ 9	$ 15
Variable Annuities [Member]
Market Risk Benefit [Line Items]
Balance as of Beginning-of-year	(662)	2,398
Balance as of beginning-of-year, before the effect of changes in non-performance risk	1,511	4,823
Issuances	1	12
Attributed fees collected	379	1,571
Benefit payments	(19)	(63)
Effect of changes in interest rates	1,406	(9,346)
Effect of changes in equity markets	(1,029)	4,293
Effect of changes in equity index volatility	(286)	(225)
In-force updates and other changes in MRBs	76	661
Effect of changes in future expected policyholder behavior		(158)
Effect of changes in other future expected assumptions		(57)
Balance as of end-of-year, before the effect of changes in non-performance risk	2,039	1,511
Effect of changes in non performance risk	(3,451)	(2,173)
Balance as of ending-of-year	(1,412)	(662)
Less: ceded MRB assets (liabilities)	(210)	294
Balance as of end-of-year, net of reinsurance	$ (1,202)	$ (956)
Weighted-average age of policyholder (years)	71 years	71 years
Market Risk Benefit, Net Amount at Risk	$ 6,268	$ 7,974