Investments - Components of the net unrealized gain on securities that is included in AOCI in the Balance Sheet (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Unrealized gain on:
Pretax	$ 1,589	$ 1,091
Deferred Tax	(334)	(229)
Net	1,255	862
Total fixed maturities
Unrealized gain on:
Pretax	2,839	1,981
Deferred Tax	(596)	(416)
Net	2,243	1,565
Fixed maturities — annuity segment
Unrealized gain on:
Pretax	2,323	1,611
Deferred Tax	(488)	(338)
Net	1,835	1,273
Fixed maturities — all other
Unrealized gain on:
Pretax	516	370
Deferred Tax	(108)	(78)
Net	408	292
Deferred policy acquisition costs — annuity segment
Unrealized gain on:
Pretax	(934)	(681)
Deferred Tax	196	143
Net	(738)	(538)
Annuity benefits accumulated
Unrealized gain on:
Pretax	(324)	(219)
Deferred Tax	68	46
Net	(256)	(173)
Life, accident and health reserves
Unrealized gain on:
Pretax	(3)	(1)
Deferred Tax	0	0
Net	(3)	(1)
Unearned revenue
Unrealized gain on:
Pretax	11	11
Deferred Tax	(2)	(2)
Net	$ 9	$ 9