Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Cash flows from operating activities:
Net income	$ 65,361	$ 41,379
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	(2,125)	32,750
Net (gain) loss on disposal of property and equipment	(224)	(490)
Depreciation and amortization	12,293	12,770
Net premium amortization on investment securities	11,426	7,913
Net gains on investment securities transactions	(26)	(295)
Net gains on sales of mortgage loans held for sale	(20,376)	(20,648)
Net gain on sale of OREO	(3,195)	(768)
OREO valuation adjustments	3,180	3,457
Net impairment (reversal of impairment) of mortgage servicing rights	(121)	(761)
Gain Loss on Sale of Mortgage Servicing	0	19
Deferred income tax expense	6,302	8,013
Net increase in cash surrender value of company-owned life insurance policies	28	(1,491)
Stock-based compensation expense	2,207	2,351
Tax benefits from stock-based compensation expense	1,578	296
Excess tax benefits from stock-based compensation	(1,488)	(187)
Originations of mortgage loans held for sale, net of sales	31,754	(2,055)
Changes in operating assets and liabilities:
Increase in interest receivable	(1,515)	(1,442)
Decrease in other assets	9,434	7,381
Decrease in accrued interest payable	(1,135)	(1,417)
Decrease in accounts payable and accrued expenses	(2,622)	(1,800)
Net cash provided by operating activities	110,736	84,937
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	(13,915)	(44,283)
Purchases of available-for-sale investment securities	(564,448)	(787,697)
Proceeds from maturities and paydowns of held-to-maturity investment securities	15,818	9,069
Proceeds from maturities and paydowns of available-for-sale investment securities	569,606	817,903
Capital distribution by unconsolidated subsidiary trust	0	1,238
Proceeds from sales of mortgage servicing rights	470	907
Extensions of credit to customers, net of repayments	(147,826)	(61,721)
Recoveries of loans charged-off	9,434	4,320
Proceeds from sales of OREO	25,185	31,800
Capital contribution to unconsolidated equity method investment	0	900
Capital contribution to unconsolidated equity method investee	(2,489)	(11,973)
Net cash used in investing activities	(108,165)	(41,337)
Cash flows from financing activities:
Net increase (decrease) in deposits	(131,786)	208,761
Net decrease in repurchase agreements	(77,675)	(55,438)
Net increase (decrease) in short-term borrowings	(22)	(1)
Repayment of junior subordinated debentures held by subsidiary trusts	0	41,238
Repayments of long-term debt	(32)	(30)
Redemption of preferred stock	(50,000)	0
Proceeds from issuance of common stock	8,680	1,326
Excess tax benefits from stock-based compensation	1,488	187
Purchase and retirement of common stock	(448)	(262)
Dividends paid to common stockholders	(11,765)	(15,448)
Dividends paid to preferred stockholders	0	(2,569)
Net cash provided by (used in) financing activities	(261,560)	95,288
Net increase (decrease) in cash and cash equivalents	(258,989)	138,888
Cash and cash equivalents at beginning of period	801,332	472,447
Cash and cash equivalents at end of period	542,343	611,335
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	30,529	12,740
Cash paid during the period for interest expense	$ 17,094	$ 24,903