Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010
Operating Activities
Net income	$ 55,615	$ 49,616
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	15,653	25,493
Depreciation and amortization	11,912	11,826
Net amortization of securities	3,142	871
Securities gains, net	(58)	(2,224)
Gains on sales of loans, net	(4,953)	(5,652)
Decrease in FDIC indemnification asset	6	0
Bargain purchase gain on acquisition	(7,456)	0
Deferred income tax provision (benefit)	4,345	(7,870)
Proceeds from sales of loans held for sale	440,980	468,040
Purchases and originations of loans held for sale	(396,536)	(450,766)
Originations and sales of mortgage servicing rights, net	(6,380)	(6,773)
Net decrease in other assets	14,388	36,481
Net decrease in other liabilities	(6,234)	(10,147)
Other operating activities, net	11,943	21,384
Net cash provided by operating activities	136,367	130,279
Investing Activities
Proceeds from calls and maturities of securities held to maturity	52,959	40,176
Proceeds from calls and maturities of securities available for sale	268,145	244,376
Proceeds from sales of securities available for sale	22,996	65,074
Purchases of securities available for sale	(471,760)	(370,865)
Net decrease in federal funds sold and securities purchased under reverse repurchase agreements	7,197	661
Net decrease in loans	117,587	202,258
Purchases of premises and equipment	(4,477)	(2,254)
Proceeds from sales of premises and equipment	395	3
Proceeds from sales of other real estate	23,742	24,246
Net cash received in business combination	78,896	0
Net cash provided by investing activities	95,680	203,675
Financing Activities
Net increase (decrease) in deposits	383,418	(49,071)
Net decrease in federal funds purchased and securities sold under repurchase agreements	(160,445)	(160,665)
Net decrease in short-term borrowings	(365,240)	(124,587)
Common stock dividends	(29,740)	(29,642)
Common stock issued-net, long-term incentive plans	(361)	1,477
Excess tax benefit from stock-based compensation arrangements	630	1,380
Net cash used in financing activities	(171,738)	(361,108)
Increase (decrease) in cash and cash equivalents	60,309	(27,154)
Cash and cash equivalents at beginning of period	161,544	213,519
Cash and cash equivalents at end of period	$ 221,853	$ 186,365