Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Cash flows from operating activities:
Net income	$ 20,044	$ 12,214
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	500	11,250
Net (gain) loss on disposal of property and equipment	(20)	42
Depreciation and amortization	4,203	4,302
Net premium amortization on investment securities	4,082	2,678
Net gains on investment securities transactions	(8)	(31)
Net gains on sales of mortgage loans held for sale	(7,898)	(5,927)
Net gain on sale of OREO	(820)	74
OREO valuation adjustments	2,305	578
Net impairment (reversal of impairment) of mortgage servicing rights	(48)	(868)
Gain Loss on Sale of Mortgage Servicing	0	19
Deferred income tax expense	1,853	(282)
Net increase in cash surrender value of company-owned life insurance policies	(429)	(462)
Stock-based compensation expense	695	643
Tax benefits from stock-based compensation expense	202	114
Excess tax benefits from stock-based compensation	(165)	(94)
Originations of mortgage loans held for sale, net of sales	17,753	(272)
Changes in operating assets and liabilities:
Increase in interest receivable	(506)	1,567
Decrease in other assets	(64)	907
Decrease in accrued interest payable	(69)	132
Decrease in accounts payable and accrued expenses	(1,861)	1,744
Net cash provided by operating activities	39,749	28,290
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	(6,347)	(7,592)
Purchases of available-for-sale investment securities	(227,040)	(222,413)
Proceeds from maturities and paydowns of held-to-maturity investment securities	3,512	2,193
Proceeds from maturities and paydowns of available-for-sale investment securities	201,621	282,083
Proceeds from sales of mortgage servicing rights	311	907
Extensions of credit to customers, net of repayments	(22,997)	10,027
Recoveries of loans charged-off	2,913	1,158
Proceeds from sales of OREO	3,957	5,691
Capital contribution to unconsolidated equity method investee	(650)	(3,453)
Net cash used in investing activities	(44,720)	68,601
Cash flows from financing activities:
Net increase (decrease) in deposits	(212,066)	83,863
Net decrease in repurchase agreements	(38,580)	(25,185)
Net increase (decrease) in short-term borrowings	(24)	(1)
Repayments of long-term debt	(10)	(9)
Redemption of preferred stock	(50,000)	0
Proceeds from issuance of common stock	3,145	1,068
Excess tax benefits from stock-based compensation	165	94
Purchase and retirement of common stock	(448)	(256)
Dividends paid to common stockholders	0	(5,135)
Dividends paid to preferred stockholders	0	(853)
Net cash provided by (used in) financing activities	(297,818)	53,586
Net increase (decrease) in cash and cash equivalents	(302,789)	150,477
Cash and cash equivalents at beginning of period	801,332	472,447
Cash and cash equivalents at end of period	498,543	622,924
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	3,376	100
Cash paid during the period for interest expense	$ 5,859	$ 8,291