CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
INTEREST INCOME:
Interest and fees on loans and leases	$ 868	$ 779
Interest and fees on loans held for sale, at fair value	3	2
Interest and fees on other loans held for sale	1	1
Investment securities	145	159
Interest-bearing deposits in banks	2	1
Total interest income	1,019	942
INTEREST EXPENSE:
Deposits	60	52
Federal funds purchased and securities sold under agreements to repurchase	1	7
Other short-term borrowed funds	11	15
Long-term borrowed funds (RBS balances of $11 and $20, respectively)	43	32
Total interest expense	115	106
Net interest income	904	836
Provision for credit losses	91	58
Net interest income after provision for credit losses	813	778
NONINTEREST INCOME:
Service charges and fees	144	135
Card fees	50	52
Trust and investment services fees	37	36
Capital markets fees	22	22
Foreign exchange and letter of credit fees	21	23
Mortgage banking fees	18	33
Bank-owned life insurance income	13	12
Securities gains, net	9	8
Net securities impairment losses recognized in earnings	(1)	(1)
Other income	17	27
Total noninterest income	330	347
NONINTEREST EXPENSE:
Salaries and employee benefits	425	419
Outside services	91	79
Occupancy	76	80
Equipment expense	65	63
Amortization of software	39	36
Other operating expense	115	133
Total noninterest expense	811	810
Income before income tax expense	332	315
Income tax expense	109	106
NET INCOME	223	209
Net income available to common stockholders	$ 216	$ 209
Weighted-average common shares outstanding:
Basic (in Shares)	528,070,648	546,291,363
Diluted (in Shares)	530,446,188	549,798,717
Per common share information:
Basic earnings (in Dollars per Share)	$ 0.41	$ 0.38
Diluted earnings (in Dollars per Share)	0.41	0.38
Dividends declared and paid (in Dollars per Share)	$ 0.10	$ 0.10