Derivative Instruments (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Credit Derivatives [Line Items]
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months	$ 17
Cash flow hedge, reclassified to earnings, net	0	$ 0
Non-performance Risk Adjustment	0
Exposure Associated With Collateralization Events	0		$ 0
Credit Default Swap, Seller [Member]
Credit Derivatives [Line Items]
Collateral Requirement If Netting Agreements Not In Place	$ 2
Indexed Annuity [Member]
Credit Derivatives [Line Items]
Derivative term	6 years