Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net income	$ 12,214	$ 9,506
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	11,250	15,000
Net loss on disposal of property and equipment	42	3
Depreciation and amortization	4,302	4,436
Net premium amortization on investment securities	2,678	2,598
Net gains on investment securities transactions	(31)	(2)
Net gains on sales of mortgage loans held for sale	(5,927)	(2,260)
Net loss (gain) on sale of OREO	74	(156)
Write-down of OREO	578	1,552
Net reversal of impairment of mortgage servicing rights	(868)	(347)
Net gain on sale of mortgage servicing rights	(19)	0
Deferred income tax benefit	(282)	(859)
Net increase in cash surrender value of company-owned life insurance policies	(462)	(489)
Stock-based compensation expense	643	411
Tax benefits from stock-based compensation expense	114	257
Excess tax benefits from stock-based compensation	(94)	(192)
Originations of mortgage loans held for sale, net of sales	(272)	27,123
Changes in operating assets and liabilities:
Increase in interest receivable	1,567	1,248
Decrease in other assets	907	7,828
Increase (decrease) in accrued interest payable	132	(1,016)
Increase in accounts payable and accrued expenses	1,744	1,702
Net cash provided by operating activities	28,290	66,343
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	(7,592)	(1,868)
Purchases of available-for-sale investment securities	(222,413)	(193,791)
Proceeds from maturities and paydowns of held-to-maturity investment securities	2,193	2,720
Proceeds from maturities and paydowns of available-for-sale investment securities	282,083	136,839
Proceeds from sales of mortgage servicing rights	907	0
Extensions of credit to customers, net of repayments	10,027	64,419
Recoveries of loans charged-off	1,158	1,305
Proceeds from sales of OREO	5,691	3,160
Capital expenditures, net of sales	(3,453)	(1,639)
Net cash provided by investing activities	68,601	11,145
Cash flows from financing activities:
Net increase in deposits	83,863	5,471
Net decrease in repurchase agreements	(25,185)	(83,199)
Net increase (decrease) in short-term borrowings	(1)	531
Repayments of long-term debt	(9)	(11)
Proceeds from issuance of common stock	1,068	37
Excess tax benefits from stock-based compensation	94	192
Purchase and retirement of common stock	(256)	(164)
Dividends paid to common stockholders	(5,135)	(4,798)
Dividends paid to preferred stockholders	(853)	(844)
Net cash (used in) provided by financing activities	53,586	(82,785)
Net increase (decrease) in cash and cash equivalents	150,477	(5,297)
Cash and cash equivalents at beginning of period	472,447	685,618
Cash and cash equivalents at end of period	622,924	680,321
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	100	0
Cash paid during the period for interest expense	$ 8,291	$ 13,061