Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating Activities
Net Income	$ 125,789	$ 120,814
Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:
Provision for Credit Losses	979	10,471
Depreciation and Amortization	10,339	10,918
Amortization of Deferred Loan and Lease Fees	(2,493)	(1,986)
Amortization and Accretion of Premiums/Discounts on Investment Securities, Net	42,633	35,899
Share-Based Compensation	5,687	2,001
Benefit Plan Contributions	(5,888)	(965)
Deferred Income Taxes	(16,793)	(8,277)
Net Gain on Sale of Proprietary Mutual Funds		(1,956)
Net Gains on Sales of Loans and Leases	(11,645)	(4,658)
Net Losses (Gains) on Investment Securities	77	(6,084)
Proceeds from Sales of Loans Held for Sale	369,481	334,883
Originations of Loans Held for Sale	(367,965)	(317,646)
Tax Benefits from Share-Based Compensation	(712)	(696)
Net Change in Other Assets and Other Liabilities	24,094	9,770
Net Cash Provided by Operating Activities	125,395	182,488
Investment Securities Available-for-Sale:
Proceeds from Prepayments and Maturities	737,377	730,294
Proceeds from Sales	44,844	682,283
Purchases	(452,430)	(1,535,348)
Investment Securities Held-to-Maturity:
Proceeds from Prepayments and Maturities	689,246	199,844
Purchases	(540,472)	(384,785)
Proceeds from Sale of Proprietary Mutual Funds		1,956
Net Change in Loans and Leases	(253,521)	(37,522)
Premises and Equipment, Net	(13,933)	(7,257)
Net Cash Provided by (Used in) Investing Activities	211,111	(350,535)
Financing Activities
Net Change in Deposits	627,924	120,018
Net Change in Short-Term Borrowings	(1,107,767)	28,786
Tax Benefits from Share-Based Compensation	712	696
Proceeds from Issuance of Common Stock	10,356	9,919
Repurchase of Common Stock	(66,245)	(82,391)
Cash Dividends Paid	(61,459)	(64,048)
Net Cash Provided by (Used in) Financing Activities	(596,479)	12,980
Net Change in Cash and Cash Equivalents	(259,973)	(155,067)
Cash and Cash Equivalents at Beginning of Period	669,909	607,547
Cash and Cash Equivalents at End of Period	409,936	452,480
Supplemental Information
Cash Paid for Interest	31,483	35,448
Cash Paid for Income Taxes	58,625	68,613
Non-Cash Investing Activities:
Transfer from Investment Securities Available-For-Sale to Investment Securities Held-To-Maturity		2,220,814
Transfer from Loans to Foreclosed Real Estate	3,230	2,067
Transfers from Loans to Loans Held for Sale		$ 8,555