Investments (Net investment income summary) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020		Dec. 31, 2019	Dec. 31, 2018
Investments, Debt and Equity Securities [Abstract]
Investment income on fixed maturities	$ 1,161		$ 1,378	$ 1,353
Net realized gains (losses)	(10)	[1]	(8)	10
Affordable housing partnerships	(66)		(98)	(58)
Other	89		97	154
Consolidated investment entities	77		94	137
Total net investment income	1,251		$ 1,463	$ 1,596
Allowance for Credit Loss	$ (27)

[1] Includes the change in the allowance for credit losses of $(27) million for the year ended December 31, 2020.