Fair Value Of Financial Instruments (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2022
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Percentage of level 3 assets at fair value in total assets measured at fair value value	7.00%		7.00%		7.00%
Percentage of level 3 liabilities at fair value in total liabilities measured at fair value	83.00%		83.00%		82.00%
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	$ (213)		$ (213)		$ (283)
Instrument-specific credit risk of liabilities measured at fair value, net [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Gain (loss) on cumulative changes in instrument-specific credit risk of liabilities elected under the fair value option	(16)		(16)		$ (45)
Gain (loss) on instrument-specific credit risk recognized in earnings	$ (20)	$ 15	$ (34)	$ 12