Accumulated Other Comprehensive Income (Details Of The Reclassification From AOCI) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (13)	$ 17
Net income (loss)	(93)	(73)
Amounts reclassified from AOCI [Member]
Net income (loss)	(19)	(3)
Unrealized gains (losses) on AFS, net [Member] | Amounts reclassified from AOCI [Member]
Net realized investment gains (losses)	(5)	0
Instrument-specific credit risk of liabilities measured at fair value, net [Member] | Amounts reclassified from AOCI [Member]
Other net realized gains (losses)	(14)	0
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 0	$ (3)