Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Operating Activities:
Net income	$ 125,171	$ 110,994
Income from discontinued operations, net of tax	0	1,995
Income from continuing operations	125,171	108,999
Adjustments to reconcile income from continuing operations to net cash provided by operating activities:
Provision for loan and lease losses	14,000	20,000
Deferred tax expense	14,192	20,884
Depreciation and amortization	81,632	59,673
Stock-based compensation	6,687	4,452
Excess tax benefits from stock-based compensation	(303)	(278)
(Gain) loss on sale and write-down of foreclosed and repossessed assets	(1,923)	4,830
Loss on sale of premises and equipment	603	1,668
Loss (gain) on fair value adjustment of private equities	641	(1,488)
Loss on fair value adjustment of derivative instruments	12	1,813
Net gain on the sale of investment securities	(3,347)	(3,823)
Net decrease in trading securities	0	11,554
Increase in cash surrender value of life insurance policies	(7,758)	(7,751)
Net (increase) decrease in loans held for sale	(20,020)	23,958
Net (increase) decrease in accrued interest receivable and other assets	(16,850)	1,768
Net (decrease) increase in accrued expenses and other liabilities	(3,682)	7,199
Net cash provided by operating activities	189,055	253,458
Investing Activities:
Net decrease (increase) in interest-bearing deposits	16,299	(34,429)
Purchases of available for sale securities	(1,009,181)	(755,911)
Proceeds from maturities and principal payments of available for sale securities	627,429	383,313
Proceeds from sales of available for sale securities	148,223	278,757
Purchases of held-to-maturity securities	(752,030)	(423,830)
Proceeds from maturities and principal payments of held-to-maturity securities	571,648	393,378
Sale of Federal Home Loan Bank and Federal Reserve Board stock	1,279	0
Net increase in loans	(586,375)	(133,167)
Purchase of life insurance	(100,000)	0
Proceeds from the sale of foreclosed properties and repossessed assets	7,453	12,572
Proceeds from the sale of premises and equipment	1,406	3,881
Purchases of premises and equipment	(14,544)	(19,708)
Net cash used for investing activities	(1,088,393)	(295,144)
Financing Activities:
Net increase (decrease) in deposits	757,412	(22,851)
Proceeds from Federal Home Loan Bank advances	2,826,265	748,934
Repayments of Federal Home Loan Bank advances	(2,625,500)	(755,487)
Net increase in securities sold under agreements to repurchase and other short-term borrowings	145,309	129,428
Repayment of long-term debt	(210,971)	(22,689)
Cash dividends paid to common shareholders	(21,906)	(9,607)
Cash dividends paid to preferred shareholders of consolidated subsidiary	0	(647)
Cash dividends paid to preferred shareholders	(1,845)	(1,846)
Exercise of stock options	856	103
Excess tax benefits from stock-based compensation	303	278
Issuance of common stock	407	590
Common stock repurchased	(2,008)	(1,342)
Common stock warrants repurchased	(385)	(16,246)
Net cash provided by financing activities	867,937	48,618
Cash Flows from Discontinued Operations:
Operating activities	0	1,995
Net cash provided by discontinued operations	0	1,995
Net (decrease) increase in cash and due from banks	(31,401)	8,927
Cash and due from banks at beginning of period	195,957	159,849
Cash and due from banks at end of period	164,556	168,776
Supplemental disclosure of cash flow information:
Interest paid	92,056	108,582
Income taxes paid	30,398	12,889
Noncash investing and financing activities:
Transfer of loans and leases, net to foreclosed properties and repossessed assets	5,474	8,088
Transfer of loans from portfolio to loans-held-for-sale	$ 13,796	$ 13,266