Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 18
Credit Default Swaps Referencing Indices, Sell Protection
Credit Derivatives
Credit Derivative, Maximum Exposure, Undiscounted	233	$ 0
Credit Risk Derivatives, at Fair Value, Net	(2)	0
Credit Default Swap, Buying Protection
Credit Derivatives
Credit Derivative, Maximum Exposure, Undiscounted	6	0
Credit Risk Derivatives, at Fair Value, Net	0	$ 0
NAIC 4 | Credit Default Swaps Referencing Indices, Sell Protection
Credit Derivatives
Credit Derivative, Maximum Exposure, Undiscounted	$ 233