Derivative Instruments (Derivative Instruments Offsetting Balance Sheet) (Details) - USD ($) $ in Millions		Sep. 30, 2023	Dec. 31, 2022
Derivative Assets [Abstract]
Derivative Fair Value Of Free Standing Derivative Asset		$ 168	$ 223
Gross Amounts Offset in the Balance Sheet		(93)	(53)
Net Amounts Presented in the Balance Sheet		75	170
Derivative Asset, Fair Value of Collateral	[1]	(75)	(170)
Net Amount		0	0
Derivative Liabilities [Abstract]
Derivative Fair Value Of Free Standing Derivative Liability		465	236
Gross Amounts Offset in the Balance Sheet		(93)	(53)
Net Amounts Presented in the Balance Sheet		372	183
Gross Amounts Not Offset in the Balance Sheet - Financial Instruments	[1]	(372)	(183)
Net Amount		$ 0	$ 0

[1] Includes initial margin posted to a central clearing partner for financial instruments and excludes the excess of collateral received/pledged from/to the counterparty.