Accumulated Other Comprehensive Income (Loss) - Components of AOCI (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019
Debt Securities, Available-for-sale [Line Items]
Fixed maturities, net of impairments	$ 2,625		$ 1,715
Derivatives	169		137
DAC/VOBA and Sales inducements adjustment on available-for-sale securities	(739)		(458)
Premium deficiency reserve adjustment	(278)		(118)
Unrealized capital gains (losses), before tax	1,777		1,276
Deferred income tax asset (liability)	(245)		(139)
Unrealized capital gains (losses), after tax	1,532		1,137
Pension and other postretirement benefits liability, net of tax	3		3
AOCI	1,535	$ 1,292	$ 1,140
Other Contract
Debt Securities, Available-for-sale [Line Items]
Reclassification from AOCI, Current Period, before Tax, Attributable to Parent	$ 22