Derivative Instruments (Effect Of Derivative Instruments On Consolidated Statements Of Operations) (Detail) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Net gain/(loss) recognized in income	$ 22	$ 9	$ 17	$ 66
Insured swaps [Member]
Derivative [Line Items]
Net gain/(loss) recognized in income			0	1
Interest Rate Swap [Member]
Derivative [Line Items]
Net gain/(loss) recognized in income	20	23	21	79
Currency swaps-VIE [Member]
Derivative [Line Items]
Net gain/(loss) recognized in income	$ 2	$ (14)	$ (4)	$ (14)