Accumulated Other Comprehensive Income (Changes In The Components Of AOCI) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Beginning balance	$ (61)	$ 21	$ (86)
Other comprehensive income (loss) before reclassification	(68)	(81)	90
Amounts reclassified from AOCI	1	(1)	17
Total other comprehensive income (loss)	(67)	(82)	107
Ending balance	(128)	(61)	21
Unrealized gains (losses) on AFS, net [Member]
Beginning balance	(22)	34	(96)
Other comprehensive income (loss) before reclassification	27	(55)	117
Amounts reclassified from AOCI	1	(1)	13
Total other comprehensive income (loss)	28	(56)	130
Ending balance	6	(22)	34
Foreign currency translation, net [Member]
Beginning balance	(39)	(13)	10
Other comprehensive income (loss) before reclassification	(95)	(26)	(27)
Amounts reclassified from AOCI	0	0	4
Total other comprehensive income (loss)	(95)	(26)	(23)
Ending balance	$ (134)	$ (39)	$ (13)