Consolidated Statements of Cash Flows (Unaudited - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Cash Flows from Operating Activities:
Net Income	$ 544.0	$ 508.4
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Investment Security Losses (Gains), net	0.7	2.1
Amortization and Accretion of Securities and Unearned Income, net	53.0	37.2
Provision for Credit Losses	(8.0)	(1.0)
Depreciation on Buildings and Equipment	47.0	44.8
Pension Plan Contributions	(11.5)	(9.1)
Change in Receivables	(71.4)	(41.5)
Change in Interest Payable	8.3	(0.7)
Change in Collateral With Derivative Counterparties, net	477.0	(1,067.1)
Other Operating Activities, net	(885.9)	(120.4)
Net Cash Provided by (Used in) Operating Activities	312.6	(507.2)
Cash Flows from Investing Activities:
Net Change in Federal Funds Sold and Securities Purchased under Agreements to Resell	(106.3)	(249.9)
Change in Interest-Bearing Deposits with Banks	116.1	(56.1)
Net Change in Federal Reserve and Other Central Bank Deposits	(1,804.9)	101.4
Purchases of Securities — Held to Maturity	(4,724.2)	(2,576.5)
Proceeds from Maturity and Redemption of Securities — Held to Maturity	4,857.7	1,235.1
Purchases of Securities — Available for Sale	(4,388.5)	(6,554.3)
Proceeds from Sale, Maturity and Redemption of Securities — Available for Sale	5,819.9	4,432.3
Change in Loans and Leases	531.8	(1,373.3)
Purchases of Buildings and Equipment	(40.1)	(32.0)
Purchases and Development of Computer Software	(179.3)	(153.8)
Change in Client Security Settlement Receivables	(662.7)	(56.0)
Acquisition of a Subsidiary, Net of Cash Received	0.0	(16.9)
Other Investing Activities, net	282.5	369.6
Net Cash Used in Investing Activities	(298.0)	(4,930.4)
Cash Flows from Financing Activities:
Change in Deposits	1,313.8	2,596.2
Change in Federal Funds Purchased	(46.1)	(45.5)
Change in Securities Sold under Agreements to Repurchase	(10.0)	18.9
Change in Short-Term Other Borrowings	(1,060.2)	1,996.2
Proceeds from Senior Notes and Long-Term Debt	350.0	0.0
Repayments of Senior Notes and Long-Term Debt	(5.3)	(2.8)
Treasury Stock Purchased	(227.7)	(281.1)
Net Proceeds from Stock Options	70.3	26.7
Cash Dividends Paid on Common Stock	(174.2)	(165.1)
Cash Dividends Paid on Preferred Stock	(26.6)	(11.7)
Other Financing Activities, net	0.1	(8.9)
Net Cash Provided by Financing Activities	184.1	4,122.9
Effect of Foreign Currency Exchange Rates on Cash	164.1	208.3
Increase (Decrease) in Cash and Due from Banks	362.8	(1,106.4)
Cash and Due from Banks at Beginning of Year	5,332.0	6,418.5
Cash and Due from Banks at End of Period	5,694.8	5,312.1
Supplemental Disclosures of Cash Flow Information:
Interest Paid	124.0	89.7
Income Taxes Paid	312.2	413.4
Transfers from Loans to OREO	5.8	10.2
Computer Software
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Amortization of Intangibles	154.7	135.8
Other Intangible Assets
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Amortization of Intangibles	$ 4.7	$ 4.3