Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES
Net income	$ 592	$ 469	$ 309
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	17	83	34
Depreciation and amortization	179	123	86
Securities losses (gains), net	25	26	25
Deferred income tax expense (benefit)	154	(8)	(30)
Net decrease (increase) in trading securities	(33)	(67)	22
Net decrease (increase) in loans held for sale	97	1	(6)
Change in other liabilities	29	1	(6)
Change in other assets	(89)	(10)	(67)
Other, net	(29)	(15)	(30)
Net cash provided by operating activities	928	596	464
CASH FLOWS FROM INVESTING ACTIVITIES
Net decrease in money market investments	683	4,749	1,837
Proceeds from maturities and paydowns of investment securities held-to-maturity	314	94	123
Purchases of investment securities held-to-maturity	(216)	(416)	(61)
Proceeds from sales, maturities, and paydowns of investment securities available-for-sale	2,412	3,787	1,681
Purchases of investment securities available-for-sale	(4,719)	(9,359)	(5,513)
Net change in loans and leases	(2,135)	(2,102)	(563)
Purchases and sales of other noninterest-bearing investments	(105)	(20)	31
Purchases of premises and equipment	(169)	(196)	(157)
Proceeds from sales of other real estate owned	8	20	25
Other, net	(8)	(7)	(18)
Net cash used in investing activities	(3,919)	(3,436)	(2,579)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase (decrease) in deposits	(614)	2,883	2,526
Net change in short-term funds borrowed	2,149	480	103
Proceeds from debt over 90 days and up to one year	5,100	0	0
Repayments of debt over 90 days and up to one year	(3,100)	0	0
Cash paid for preferred stock redemption	(144)	(126)	(176)
Repayments of long-term debt	(153)	(280)	(288)
Company common stock repurchased	(332)	(97)	(7)
Proceeds from Issuance of common stock	25	25	22
Dividends paid on common and preferred stock	(129)	(108)	(108)
Other, net	0	2	(1)
Net cash provided by financing activities	2,802	2,779	2,071
Net decrease in cash and due from banks	(189)	(61)	(44)
Cash and due from banks at beginning of period	737	798	842
Cash and due from banks at end of period	548	737	798
Interest paid	118	83	102
Net cash paid for income taxes	246	214	132
Loans held for investment transfered to other real estate owned	6	15	12
Loans held for investment reclassified to loans held for sale, net	25	50	5
Available for sale securities purchased, not settled	5	395	0
Adjusted cost of HTM securities reclassifed as AFS securities	$ 0	$ 0	$ 79