Accumulated Other Comprehensive Income (Details Of The Reclassification From AOCI) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 63	$ 78	$ 69
Income (loss) before income taxes	289	641	416
Provision (benefit) for income taxes	109	72	166
Net income (loss)	180	569	250
Amounts reclassified from AOCI [Member]
Net income (loss)	1	(17)	16
Unrealized gains (losses) on AFS, net [Member] | Amounts reclassified from AOCI [Member]
Net gains (losses) on financial instruments at fair value and foreign exchange	11	(17)	23
Other-than-temporary impairments recognized in accumulated other comprehensive income (loss)	(4)	0	0
Net investment income	(4)	(4)	(5)
Income (loss) before income taxes	3	(21)	18
Provision (benefit) for income taxes	2	(8)	7
Net income (loss)	1	(13)	11
Foreign currency translation, net [Member] | Amounts reclassified from AOCI [Member]
Net gains (losses) on financial instruments at fair value and foreign exchange	$ 0	$ (4)	$ 5