Consolidated Balance Sheets (USD $) In Millions, except Share data in Thousands, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Assets
Cash and due from banks	$ 1,336	$ 1,562
Interest-bearing deposits with banks	2,464	2,646
Federal funds sold and securities purchased under resale agreements or similar arrangements	252	136
Segregated cash due from banks	20	20
Trading securities at fair value	589	534
Securities available for sale at fair value ($1,621 and $1,577 covered by FDIC loss share at March 31, 2012 and December 31, 2011, respectively)	24,380	22,313
Securities held to maturity (fair value of $13,507 and $14,098 at March 31, 2012 and December 31, 2011, respectively)	13,485	14,094
Loans held for sale	2,525	3,736
Loans and leases ($4,532 and $4,867 covered by FDIC loss share at March 31, 2012 and December 31, 2011, respectively)	108,161	107,469
Allowance for loan and lease losses	(2,181)	(2,256)
Loans and leases, net of allowance for loan and lease losses	105,980	105,213
FDIC loss share receivable	949	1,100
Premises and equipment	1,822	1,855
Goodwill	6,077	6,078
Core deposit and other intangible assets	422	444
Residential mortgage servicing rights at fair value	696	563
Other assets ($403 and $415 of foreclosed property and other assets covered by FDIC loss share at March 31, 2012 and December 31, 2011, respectively)	13,755	14,285
Total assets	174,752	174,579
Deposits:
Noninterest-bearing deposits	27,410	25,684
Interest-bearing deposits	96,747	99,255
Total deposits	124,157	124,939
Federal funds purchased, securities sold under repurchase agreements and short-term borrowed funds	3,436	3,566
Long-term debt	22,768	21,803
Accounts payable and other liabilities	6,509	6,791
Total liabilities	156,870	157,099
Commitments and contingencies (Note 13)
Shareholders' equity:
Common stock, $5 par	3,492	3,486
Additional paid-in capital	5,880	5,873
Retained earnings	9,064	8,772
Accumulated other comprehensive loss, net of deferred income taxes	(616)	(713)
Noncontrolling interests	62	62
Total shareholders' equity	17,882	17,480
Total liabilities and shareholders' equity	$ 174,752	$ 174,579
Common shares outstanding	698,454	697,143
Common shares authorized	2,000,000	2,000,000
Preferred shares authorized	5,000	5,000