Variable Annuity and Insurance Guarantees (Liability Rollforward) (Details) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019
GMDB and GGU [Member]
Changes in Additional Liabilities for Variable Annuity and Insurance Guarantees
Balance, at the beginning of the period		$ (16)	$ (19)
Incurred claims		(5)
Paid claims		(2)	(2)
Balance, at the end of the period		(19)	(17)
GMIB [Member]
Changes in Additional Liabilities for Variable Annuity and Insurance Guarantees
Balance, at the beginning of the period		(7)	(8)
Incurred claims		(2)	(1)
Balance, at the end of the period		(9)	(7)
GMWB [Member]
Changes in Additional Liabilities for Variable Annuity and Insurance Guarantees
Balance, at the beginning of the period		(1,462)	(875)
Incurred claims	[1]	(2,437)	(104)
Balance, at the end of the period		(3,899)	(771)
GMAB [Member]
Changes in Additional Liabilities for Variable Annuity and Insurance Guarantees
Balance, at the beginning of the period		(39)	(19)
Incurred claims	[1]	(127)	(26)
Balance, at the end of the period		(88)	(45)
UL [Member]
Changes in Additional Liabilities for Variable Annuity and Insurance Guarantees
Balance, at the beginning of the period		(758)	(659)
Incurred claims		(32)	(34)
Paid claims		(12)	(17)
Balance, at the end of the period		$ (778)	$ (676)

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