Deposits and Borrowings - Schedule of Components of Interest Expense on Short-Term Borrowings and Long-Term Debt (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Short-term borrowings:
Federal funds purchased and securities loaned or sold under agreements to repurchase	$ 2	$ 1	$ 2
FHLB advances	0	9	19
Total short-term borrowings	2	10	21
Long-term debt:
Securitized debt obligations	216	151	145
Senior and subordinated notes	476	330	299
Other long-term borrowings	111	43	26
Total long-term debt	803	524	470
Total interest expense	$ 805	$ 534	$ 491