Schedule II. Condensed Financial Information of Registrant (Parent Company) (Schedule of Condensed Financial Information of Registrant, Statements of Operations and Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenues
Net investment income									$ 1,935	$ 2,118	$ 1,817
Net investment (losses) gains									(54)	29	(52)
Total revenues	$ 2,931	$ 2,820	$ 2,766	$ 2,291	$ 2,777	$ 2,685	$ 2,610	$ 2,695	10,808	10,767	10,134
Expenses
Interest									122	131	138
Income tax benefit									(131)	(223)	(151)
Net income	$ 387	$ 213	$ 151	$ (61)	$ 273	$ 107	$ 278	$ 342	690	1,000	813
Total comprehensive income (loss)									1,442	1,929	(81)
Parent Company
Revenues
Net investment income									3	13	10
Net investment (losses) gains									(20)	(21)	0
Total revenues									(17)	(8)	10
Expenses
Administrative and general									1	1	1
Interest									122	131	135
Total expenses									123	132	136
Loss from operations before income taxes and equity in net income of subsidiaries									(140)	(140)	(126)
Income tax benefit									18	21	9
Loss before equity in net income of subsidiaries									(122)	(119)	(117)
Equity in net income of subsidiaries									812	1,119	930
Net income									690	1,000	813
Equity in other comprehensive income (loss) of subsidiaries									752	929	(894)
Total comprehensive income (loss)									$ 1,442	$ 1,929	$ (81)