DAC, VOBA, DSI, and DFEL (DFEL) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Changes in DFEL [Abstract]
Balance as of beginning-of-year	$ 2,763	$ 1,429	$ 1,855
Business recaptured through reinsurance	5
Deferrals	1,092	874	753
Amortization, net of interest:
Amortization, excluding unlocking, net of interest	(533)	(474)	(383)
Unlocking	(426)	(52)	(3)
Adjustment related to realized (gains) losses	(11)	(19)	(18)
Adjustment related to unrealized (gains) losses	(2,244)	1,005	(775)
Balance as of end-of-year	$ 646	$ 2,763	$ 1,429