Consolidated Statements Of Cash Flows - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES
Net income for the period	$ 160	$ 127	$ 469	$ 332
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	1	16	29	82
Depreciation and amortization	47	34	131	88
Share-based Compensation	4	6	21	22
Deferred income tax expense (benefit)	(4)	2	4	(9)
Net decrease (increase) in trading securities	5	11	59	(60)
Net decrease (increase) in loans held for sale	(18)	(12)	71	(9)
Change in other liabilities	84	52	63	215
Change in other assets	(42)	(4)	(9)	(222)
Other, net	(10)	(19)	(35)	(24)
Net cash provided by operating activities	227	213	803	415
CASH FLOWS FROM INVESTING ACTIVITIES
Net decrease (increase) in money market investments	363	(389)	748	3,563
Proceeds from maturities and paydowns of investment securities held-to-maturity	83	34	249	66
Purchases of investment securities held-to-maturity	(54)	(35)	(127)	(235)
Proceeds from sales, maturities, and paydowns of investment securities available-for-sale	615	683	1,775	3,257
Purchases of investment securities available-for-sale	(535)	(1,607)	(4,001)	(5,974)
Net change in loans and leases	(475)	(58)	(1,511)	(1,956)
Net change in other noninterest-bearing investments	14	(26)	(89)	(29)
Purchases of premises and equipment	(39)	(51)	(133)	(143)
Proceeds from sales of other real estate owned	3	6	7	15
Other, net	1	2	5	5
Net cash used in investing activities	(24)	(1,441)	(3,077)	(1,431)
CASH FLOWS FROM FINANCING ACTIVITIES
Net increase (decrease) in deposits	(278)	575	(1,136)	496
Net change in short-term funds borrowed	(718)	845	1,297	768
Proceeds from debt over 90 days and up to one year	1,850	0	3,600	0
Repayments of debt over 90 days and up to one year	(850)	0	(1,100)	0
Cash paid for preferred stock redemption	0	0	(144)	(126)
Repayments of long-term debt	0	(129)	(153)	(244)
Proceeds from Issuance of Common Stock	2	5	20	8
Dividends paid on common and preferred stock	(34)	(31)	(89)	(81)
Company common stock repurchased	(115)	(45)	(217)	(51)
Other, Net	0	1	0	1
Net cash provided by (used in) financing activities	(143)	1,221	2,078	771
Net increase (decrease) in cash and due from banks	60	(7)	(196)	(245)
Cash and due from banks at beginning of period	481	560	737	798
Cash and due from banks at end of period	541	553	541	553
Cash paid for interest	27	18	79	61
Net cash paid for income taxes	84	53	206	154
Loans Held for Investment Transferred to Other Real Estate Owned	1	6	5	13
Loans Held for Investment Reclassified to Loans Held for Sale, Net	1	40	14	36
Available for sale securities purchased, not settled	25	0	81	0
Held to Maturity Securities Purchased, Not Settled	$ 0	$ 0	$ 31	$ 0