Consolidated Statement 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	$ 811.8		$ 731.3		$ 687.3
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Investment Security Losses (Gains), net	4.3	[1]	1.5	[1]	1.7	[1]
Amortization and Accretion of Securities and Unearned Income, net	34.8		44.7		(11.7)
Provision for Credit Losses	6.0		20.0		25.0
Depreciation on Buildings and Equipment	90.6		92.3		88.3
Change in Accrued Income Taxes	55.2		(31.5)		18.5
Pension Plan Contributions	(18.7)		(20.7)		(112.3)
Deferred Income Tax Provision	(36.4)		66.6		79.7
Change in Receivables	20.9		(206.2)		(41.9)
Change in Interest Payable	(4.5)		(11.2)		(10.0)
Change in Collateral With Derivative Counterparties, net	(359.2)		(250.6)		(127.9)
Other Operating Activities, net	86.1		176.9		16.6
Net Cash Provided by Operating Activities	936.0		839.3		814.4
CASH FLOWS FROM INVESTING ACTIVITIES
Net Change in Federal Funds Sold and Securities Purchased under Agreements to Resell	(533.1)		(468.8)		60.5
Change in Interest-Bearing Deposits with Banks	3,297.2		(782.1)		(2,107.1)
Net Change in Federal Reserve Deposits	(4,474.8)		(5,292.1)		5,829.0
Purchases of Securities - Held to Maturity	(7,138.7)		(5,715.5)		(3,798.5)
Proceeds from Maturity and Redemption of Securities - Held to Maturity	4,907.7		5,853.9		2,220.9
Purchases of Securities - Available for Sale	(12,668.0)		(8,168.0)		(19,546.4)
Proceeds from Sale, Maturity and Redemption of Securities - Available for Sale	11,476.6		8,456.4		21,183.3
Change in Loans and Leases	(2,288.3)		17.8		(469.6)
Purchases of Buildings and Equipment	(81.9)		(91.9)		(73.3)
Purchases and Development of Computer Software	(327.6)		(293.0)		(239.2)
Change in Client Security Settlement Receivables	(224.1)		690.6		(1,270.8)
Other Investing Activities, net	(157.4)		109.4		(161.2)
Net Cash (Used in) Provided by Investing Activities	(8,212.4)		(5,683.3)		1,627.6
CASH FLOWS FROM FINANCING ACTIVITIES
Change in Deposits	8,487.7		2,938.9		(1,269.7)
Change in Federal Funds Purchased	(32.2)		184.9		(35.1)
Change in Securities Sold under Agreements to Repurchase	(32.2)		217.5		(499.0)
Change in Short-Term Other Borrowings	(164.3)		1,258.8		(435.5)
Proceeds from Senior Notes and Long-Term Debt			750.0		500.0
Repayments of Senior Notes and Long-Term Debt	(640.0)		(804.4)		(923.7)
Contingent Consideration Liability Payment	(55.3)
Proceeds from Issuance of Preferred Stock - Series C	388.5
Treasury Stock Purchased	(480.7)		(309.7)		(162.4)
Net Proceeds from Stock Options	127.5		146.2		106.8
Cash Dividends Paid on Common Stock	(302.9)		(220.6)		(354.3)
Other Financing Activities, net	(222.4)		226.7
Net Cash Provided by (Used in) Financing Activities	7,073.7		4,388.3		(3,072.9)
Effect of Foreign Currency Exchange Rates on Cash	90.9		(134.6)		68.3
Decrease in Cash and Due from Banks	(111.8)		(590.3)		(562.6)
Cash and Due from Banks at Beginning of Year	3,162.4		3,752.7		4,315.3
Cash and Due from Banks at End of Year	3,050.6		3,162.4		3,752.7
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest Paid	186.5		231.9		307.4
Income Taxes Paid	279.2		262.6		188.5
Transfers from Loans to OREO	21.4		24.7		48.5
Computer Software
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Amortization of Intangibles	225.6		205.1		180.8
Other Intangible Assets
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Amortization of Intangibles	$ 19.5		$ 21.1		$ 20.3

[1] Changes in Other-Than-Temporary-Impairment (OTTI) Losses $ (4.9 ) $ - $ (2.7 ) Noncredit-related OTTI Losses Recorded in (Reclassified from) OCI 0.7 - (0.6 ) Other Security Gains (Losses), net (0.1 ) (1.5 ) 1.6