Investments (Other Invested Assets - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Investments, Debt and Equity Securities [Abstract]
Carrying value of Tax Credits	$ 1,300	$ 1,700
Losses From Tax Credits	$ 240	$ 257	$ 259