Consolidated Statements of Cash Flows (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash Flows From Operating Activities:
Net income	$ 2,226	$ 1,729	$ 2,028
Adjustments to reconcile net income to net cash from operating activities:
Provision for credit losses	251	592	1,057
Adjustment to income tax provision	(39)	516	0
Depreciation	333	315	281
Amortization of intangibles	91	106	110
Deferred tax expense	127	288	419
Equity-based compensation	102	96	97
(Gain) loss on securities, net	3	(51)	12
Net write-downs/losses on foreclosed property	22	28	168
Net change in operating assets and liabilities:
LHFS	(201)	2,445	(433)
Other assets	280	92	(210)
Accounts payable and other liabilities	(4)	(812)	346
Other, net	67	(5)	(161)
Net cash from operating activities	3,258	5,339	3,714
Cash Flows From Investing Activities:
Proceeds from sales of AFS securities	1,309	2,209	303
Proceeds from maturities, calls and paydowns of AFS securities	3,915	6,214	4,396
Purchases of AFS securities	(3,685)	(6,463)	(7,026)
Proceeds from maturities, calls and paydowns of HTM securities	1,866	2,863	5,536
Purchases of HTM securities	(4,030)	(7,399)	(5,055)
Originations and purchases of loans and leases, net of principal collected	(5,041)	(3,077)	(6,651)
Net cash from divestitures	0	522	0
Net cash from business combinations	1,025	(6)	675
Proceeds from sales of foreclosed property	239	394	799
Other, net	339	503	(24)
Net cash from investing activities	(4,063)	(4,240)	(7,047)
Cash Flows From Financing Activities:
Net change in deposits	337	(5,600)	4,676
Net change in short-term borrowings	(421)	1,274	(702)
Proceeds from issuance of long-term debt	5,510	4,164	2,327
Repayment of long-term debt	(3,912)	(1,634)	(5,112)
Net proceeds from preferred stock transactions	0	487	2,116
Cash dividends paid on common stock	(666)	(765)	(531)
Cash dividends paid on preferred stock	(148)	(147)	(33)
Other, net	265	248	55
Net cash from financing activities	965	(1,973)	2,796
Net Change in Cash and Cash Equivalents	160	(874)	(537)
Cash and Cash Equivalents at Beginning of Period	2,165	3,039	3,576
Cash and Cash Equivalents at End of Period	2,325	2,165	3,039
Supplemental Disclosure of Cash Flow Information:
Cash paid during the period for interest	765	918	1,120
Cash paid during the period for income taxes	322	677	347
Noncash investing activities:
Transfers of loans to foreclosed assets	547	609	770
Transfers of loans held for investment to LHFS	$ 684	$ 0	$ 0