Deferred Acquisition Costs, Deferred Sales Inducements and Value of Business Acquired - Roll Forward of DAC, DSI, and VOBA (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
DAC
Beginning balance			$ 3,274	$ 3,921
Additions			281	354
Amortization			56	(472)
Impact of unrealized investment (gains) losses			0	(300)
Ending balance	$ 3,623	$ 3,503	3,623	3,503
DSI
Beginning balance			820	799
Additions			83	130
Deferred sales inducement amortization expense excluding unlocking			(11)	18
Amortization	21	(13)	11	(18)
Impact of unrealized investment (gains) losses			(4)	(98)
Ending balance	915	813	915	813
VOBA
Beginning balance			914	1,187
Additions			0	0
Amortization			(4)	(20)
Impact of unrealized investment (gains) losses			15	(159)
Ending balance	930	1,008	930	1,008
Total
Beginning balance			5,008	5,907
Additions			364	484
Amortization			63	(510)
Impact of unrealized investment (gains) losses			11	(557)
Ending balance	$ 5,468	$ 5,324	5,468	$ 5,324
Accounting Standards Update 2016-13 [Member]
DAC
Deferred Policy Acquisition Costs, Period Increase (Decrease)			12
DSI
Deferred Sales Inducements, Period Increase (Decrease)			5
VOBA
Present Value of Future Insurance Profits, Period Increase (Decrease)			5
Total
Additions			$ 22

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