Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011
Assets:
Cash and due from banks	$ 164,556	$ 195,957
Interest-bearing deposits	79,763	96,062
Securities available for sale, at fair value	3,120,354	2,874,764
Securities held-to-maturity (fair value of $3,321,317and $3,130,546)	3,142,160	2,973,727
Federal Home Loan Bank and Federal Reserve Bank stock, at cost	142,595	143,874
Loans held for sale	91,207	57,391
Loans and leases	11,727,652	11,225,404
Allowance for loan and lease losses	(186,089)	(233,487)
Loans and leases, net	11,541,563	10,991,917
Deferred tax asset, net	74,098	105,665
Premises and equipment, net	135,394	147,379
Goodwill	529,887	529,887
Other intangible assets, net	11,512	15,690
Cash surrender value of life insurance policies	414,797	307,039
Prepaid FDIC premiums	21,673	37,946
Accrued interest receivable and other assets	260,103	237,042
Total assets	19,729,662	18,714,340
Liabilities and Equity:
Non-interest-bearing	2,786,525	2,473,693
Interest-bearing	11,626,912	11,182,332
Total deposits	14,413,437	13,656,025
Securities sold under agreements to repurchase and other short-term borrowings	1,310,015	1,164,706
Federal Home Loan Bank advances	1,452,660	1,252,609
Long-term debt	335,678	552,589
Accrued expenses and other liabilities	234,194	242,637
Total liabilities	17,745,984	16,868,566
Shareholders' equity:
Common stock, $.01 par value; Authorized - 200,000,000 shares Issued - 90,728,276 and 90,709,350 shares	907	907
Paid-in capital	1,145,392	1,145,346
Retained earnings	962,594	865,427
Less: Treasury stock, at cost (3,269,141 and 3,493,915 shares)	(124,877)	(134,641)
Accumulated other comprehensive loss, net	(29,277)	(60,204)
Total equity	1,983,678	1,845,774
Total liabilities and equity	19,729,662	18,714,340
Series A Preferred Stock [Member]
Shareholders' equity:
Preferred stock, $.01 par value; Authorized - 3,000,000 shares: Series A issued and outstanding - 28,939 shares	$ 28,939	$ 28,939