Investments (Investment Income Realized Investment Gains And Losses) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investment income:
Interest	$ 446	$ 445	$ 445
Dividends	201	181	170
Other	12	5	4
Total	659	631	619
Less investment expenses	13	12	10
Total	646	619	609
Gain (Loss) on Sale of Investments	1,640	(408)	148
Unrealized Gain (Loss) on Investments		(404)
Investment gains and losses, net:
Other	(3)	(12)	9
Total	1,650	(402)	148
Fixed Maturities
Investment gains and losses, net:
Gross realized gains	13	12	25
Gross realized losses	(3)	(2)	0
Other-than-temporary impairments	(9)	(5)	(6)
Total	1	5	19
Equity Securities
Investment income:
Gain (Loss) on Sale of Investments	26	9	0
Unrealized Gain (Loss) on Investments	1,626	(404)	0
Investment gains and losses, net:
Gross realized gains	0	0	195
Gross realized losses	0	0	(72)
Other-than-temporary impairments	0	0	(3)
Total	$ 1,652	$ (395)	$ 120