Variable Annuity and Insurance Guarantees (Liability Rollforward) (Details 4) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
GMDB and GGU [Member]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross
Balance, at the beginning of the period		$ 16	$ 19	$ 17
Incurred claims		15	2	8
Paid claims		(7)	(5)	(6)
Balance, at the end of the period		24	16	19
GMIB [Member]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross
Balance, at the beginning of the period		7	8	6
Incurred claims			(1)	2
Paid claims		(1)	0	0
Balance, at the end of the period		6	7	8
GMWB [Member]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross
Balance, at the beginning of the period		1,462	875	463
Incurred claims	[1]	1,587	587	412
Paid claims		0	0	0
Balance, at the end of the period		3,049	1,462	875
GMAB [Member]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross
Balance, at the beginning of the period		(39)	(19)	(80)
Incurred claims	[1]	40	(20)	61
Paid claims		0	0	0
Balance, at the end of the period		1	(39)	(19)
UL [Member]
Liabilities for Guarantees on Long-Duration Contracts, Guaranteed Benefit Liability, Gross
Balance, at the beginning of the period		758	659	489
Incurred claims		209	141	201
Paid claims		(51)	(42)	(31)
Balance, at the end of the period		$ 916	$ 758	$ 659

[1] The incurred claims for GMWB and GMAB include the change in the fair value of the liabilities (contra liabilities) less paid claims.