Accumulated Other Comprehensive Income (Details Of The Reclassification From AOCI) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Income (loss) before income taxes	$ (333)	$ (19)
Net income (loss)	(333)	(21)
Amounts reclassified from AOCI [Member]
Net income (loss)	1	7
Unrealized gains (losses) on AFS, net [Member] \| Amounts reclassified from AOCI [Member]
Net gains (losses) on financial instruments at fair value and foreign exchange	3	39
Net investment losses related to OTTI	0	(28)
Income (loss) before income taxes	3	11
Instrument-specific credit risk of liabilities measured at fair value, net [Member] \| Amounts reclassified from AOCI [Member]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ (2)	$ (4)

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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