Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
CASH FLOWS FROM OPERATING ACTIVITIES
Net Income	$ 1,032.5	$ 973.8	$ 811.8
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Investment Security Losses, net	3.2	0.3	4.3
Amortization and Accretion of Securities and Unearned Income, net	100.9	53.3	34.8
Provision for Credit Losses	(26.0)	(43.0)	6.0
Depreciation on Buildings and Equipment	89.2	90.4	90.6
Amortization of Intangibles	8.8	10.9	19.5
Change in Accrued Income Taxes	(129.0)	206.8	55.2
Pension Plan Contributions	(12.8)	(21.1)	(18.7)
Deferred Income Tax Provision	(175.8)	(146.2)	(36.4)
Change in Receivables	(129.2)	(16.2)	20.9
Change in Interest Payable	(0.1)	(8.2)	(4.5)
Change in Collateral With Derivative Counterparties, net	(180.4)	801.4	(359.2)
Other Operating Activities, net	653.4	(318.1)	86.1
Net Cash Provided by Operating Activities	1,510.0	1,834.4	936.0
CASH FLOWS FROM INVESTING ACTIVITIES
Net Change in Federal Funds Sold and Securities Purchased under Agreements to Resell	(372.9)	(549.8)	(533.1)
Change in Interest-Bearing Deposits with Banks	1,906.1	284.9	1,198.0
Net Change in Federal Reserve and Other Central Bank Deposits	(4,124.2)	558.6	(2,397.8)
Purchases of Securities – Held to Maturity	(8,573.2)	(8,075.5)	(7,138.7)
Proceeds from Maturity and Redemption of Securities – Held to Maturity	4,026.5	6,628.3	4,907.7
Purchases of Securities – Available for Sale	(14,741.9)	(11,490.3)	(12,668.0)
Proceeds from Sale, Maturity and Redemption of Securities – Available for Sale	11,317.3	8,576.1	11,476.6
Change in Loans and Leases	(471.0)	(1,581.0)	(2,288.3)
Purchases of Buildings and Equipment	(111.3)	(98.5)	(81.9)
Purchases and Development of Computer Software	(362.1)	(335.0)	(327.6)
Change in Client Security Settlement Receivables	1,105.0	(605.0)	(224.1)
Acquisition of a Subsidiary, Net of Cash Acquired	(16.9)	0.0	0.0
Other Investing Activities, net	226.5	(212.9)	(157.4)
Net Cash Used in Investing Activities	(10,192.1)	(6,900.1)	(8,234.6)
CASH FLOWS FROM FINANCING ACTIVITIES
Change in Deposits	6,737.4	8,105.7	8,487.7
Change in Federal Funds Purchased	(146.7)	(581.4)	(32.2)
Change in Securities Sold under Agreements to Repurchase	(72.9)	(338.5)	(32.2)
Change in Short-Term Other Borrowings	1,073.5	2,312.8	(164.3)
Repayments of Senior Notes and Long-Term Debt	(6.7)	(231.0)	(640.0)
Contingent Consideration Liability Payment	0.0	0.0	(55.3)
Proceeds from Issuance of Preferred Stock – Series C and Series D	493.5	0.0	388.5
Treasury Stock Purchased	(411.1)	(496.9)	(480.7)
Net Proceeds from Stock Options	233.8	94.0	127.5
Cash Dividends Paid on Common Stock	(333.0)	(321.4)	(302.9)
Cash Dividends Paid on Preferred Stock	(23.4)	(27.0)	0.0
Other Financing Activities, net	(7.5)	17.8	(222.4)
Net Cash Provided by Financing Activities	7,536.9	8,534.1	7,073.7
Effect of Foreign Currency Exchange Rates on Cash	58.7	(70.9)	86.9
Increase (Decrease) in Cash and Due from Banks	(1,086.5)	3,397.5	(138.0)
Cash and Due from Banks at Beginning of Year	6,418.5	3,021.0	3,159.0
Cash and Due from Banks at End of Year	5,332.0	6,418.5	3,021.0
SUPPLEMENTAL DISCLOSURES OF CASH FLOW INFORMATION
Interest Paid	181.6	161.6	186.5
Income Taxes Paid	754.2	390.0	279.2
Transfers from Loans to OREO	14.2	13.0	21.4
Computer Software
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Amortization of Intangibles	275.3	250.3	225.6
Other Intangible Assets
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities
Amortization of Intangibles	$ 8.8	$ 10.9	$ 19.5