Investments (Changes in Net Unrealized Investment Gains (Losses)) (Details) $ in Millions	9 Months Ended
	Sep. 30, 2021 USD ($)
Investments, Debt and Equity Securities [Abstract]
Unrealized investment gains (losses), beginning of period	$ 5,761
Unrealized investment gains (losses) during the period	(3,188)
Unrealized investment gains (losses) relating to: Future policy benefits	1,278
Unrealized investment gains (losses) relating to: DAC, VOBA and DSI	103
Unrealized investment gains (losses) relating to: Deferred income tax benefit (expense)	379
Unrealized investment gains (losses), end of period	4,333
Change in net unrealized investment gains (losses)	$ (1,428)