Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Pre-tax
Other comprehensive income (loss)	$ (472)	$ 261	$ (1,760)	$ 1,122
Tax
Other comprehensive income (loss)	100	(56)	374	(239)
After-tax
Other comprehensive income (loss)	(372)	205	(1,386)	883
Unrealized net capital gains and losses
Pre-tax
Unrealized net holding gains and losses arising during the period, net of related offsets	(343)	414	(1,350)	1,777
Less: reclassification adjustment of realized capital gains and losses	84	233	367	689
Other comprehensive income (loss)	(427)	181	(1,717)	1,088
Tax
Unrealized net holding gains and losses arising during the period, net of related offsets	73	(88)	288	(376)
Less: reclassification adjustment of realized capital gains and losses	(18)	(49)	(77)	(145)
Other comprehensive income (loss)	91	(39)	365	(231)
After-tax
Unrealized net holding gains and losses arising during the period, net of related offsets	(270)	326	(1,062)	1,401
Less: reclassification adjustment of realized capital gains and losses	66	184	290	544
Other comprehensive income (loss)	(336)	142	(1,352)	857
Unrealized foreign currency translation adjustments
Pre-tax
Other comprehensive income (loss)	(26)	32	13	(6)
Tax
Other comprehensive income (loss)	5	(7)	(3)	1
After-tax
Other comprehensive income (loss)	(21)	25	10	(5)
Unamortized pension and other postretirement prior service credit
Pre-tax
Other comprehensive income (loss)	(19)	48	(56)	40
Tax
Other comprehensive income (loss)	4	(10)	12	(9)
After-tax
Other comprehensive income (loss)	$ (15)	$ 38	$ (44)	$ 31