CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2017	Jun. 30, 2016
OPERATING ACTIVITIES
Net income		$ 638	$ 466
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses		166	181
Originations of mortgage loans held for sale		(1,394)	(1,135)
Proceeds from sales of mortgage loans held for sale		1,544	1,022
Purchases of commercial loans held for sale		(1,001)	(735)
Proceeds from sales of commercial loans held for sale		946	739
Amortization of terminated cash flow hedges, net		1	16
Depreciation, amortization and accretion		257	245
Mortgage servicing rights valuation (recovery) charge-off		(1)	4
Securities impairment		5	8
Deferred income taxes		(20)	94
Share-based compensation		27	11
Net gain on sales of:
Debt securities		(7)	(13)
Other investment securities		(1)	0
Premises and equipment		0	(2)
Decrease (increase) in other assets		32	(450)
(Decrease) increase in other liabilities		(655)	253
Net cash provided by operating activities		537	704
Investment securities:
Purchases of securities available for sale		(2,282)	(2,355)
Proceeds from maturities and paydowns of securities available for sale		1,670	1,611
Proceeds from sales of securities available for sale		407	375
Purchases of securities held to maturity		(171)	0
Proceeds from maturities and paydowns of securities held to maturity		277	290
Purchases of other investment securities, at fair value		(174)	(114)
Proceeds from sales of other investment securities, at fair value		172	109
Purchases of other investment securities, at cost		(243)	(62)
Proceeds from sales of other investment securities, at cost		409	52
Net decrease (increase) in interest-bearing deposits in banks		6	(371)
Net increase in loans and leases		(1,785)	(5,045)
Net increase in bank-owned life insurance		(24)	(23)
Premises and equipment:
Purchases		(64)	(22)
Proceeds from sales		0	3
Capitalization of software		(83)	(85)
Net cash used in investing activities		(1,885)	(5,637)
FINANCING ACTIVITIES
Net increase in deposits		3,809	3,718
Net decrease in federal funds purchased and securities sold under agreements to repurchase		(719)	(85)
Net decrease in other short-term borrowed funds		(1,208)	(1,370)
Proceeds from issuance of long-term borrowed funds		10,109	6,995
Repayments of long-term borrowed funds		(9,751)	(3,631)
Treasury stock purchased		(260)	0
Dividends declared and paid to common stockholders		(143)	(117)
Dividends declared and paid to preferred stockholders		(7)	(7)
Payments of employee tax withholding for share-based compensation		(19)	0
Net cash provided by financing activities		1,811	5,503
Increase in cash and cash equivalents	[1]	463	570
Cash and cash equivalents at beginning of period	[1]	3,704	3,085
Cash and cash equivalents at end of period	[1]	$ 4,167	$ 3,655

[1] Cash and cash equivalents includes cash and due from banks and interest-bearing cash and due from banks as reflected on the Consolidated Balance Sheets.