Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities:
Net income	$ 21,393	$ 20,044
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for loan losses	(5,000)	500
Net (gain) loss on disposal of property and equipment	(13)	(20)
Depreciation and amortization	3,896	4,203
Net premium amortization on investment securities	3,371	4,082
Net gains on investment securities transactions	(71)	(8)
Net gains on sales of mortgage loans held for sale	(3,323)	(7,898)
Net gain on sale of OREO	(435)	(820)
OREO valuation adjustments	0	2,305
Net impairment (reversal of impairment) of mortgage servicing rights	(45)	(48)
Deferred income tax expense	2,630	1,853
Net increase in cash surrender value of company-owned life insurance policies	(852)	(429)
Stock-based compensation expense	712	695
Tax benefits from stock-based compensation expense	989	202
Excess tax benefits from stock-based compensation	(982)	(165)
Originations of loans held for sale	151,911	371,684
Proceeds from sales of loans held for sale	157,141	389,437
Changes in operating assets and liabilities:
Increase in interest receivable	(685)	(506)
Decrease in other assets	(1,083)	(64)
Decrease in accrued interest payable	(10)	(69)
Decrease in accounts payable and accrued expenses	(3,694)	(1,861)
Net cash provided by operating activities	22,028	39,749
Cash flows from investing activities:
Purchases of held-to-maturity investment securities	0	(6,347)
Purchases of available-for-sale investment securities	(95,077)	(227,040)
Proceeds from maturities and paydowns of held-to-maturity investment securities	2,185	3,512
Proceeds from maturities and paydowns of available-for-sale investment securities	160,337	201,621
Purchases of company-owned life insurance	(15,000)	0
Proceeds from sales of mortgage servicing rights	266	311
Extensions of credit to customers, net of repayments	(28,580)	(22,997)
Recoveries of loans charged-off	3,822	2,913
Proceeds from sales of OREO	2,760	3,957
Capital contribution to unconsolidated equity method investee	(3,142)	(650)
Net cash used in investing activities	27,571	(44,720)
Cash flows from financing activities:
Net increase (decrease) in deposits	1,387	(212,066)
Net decrease in repurchase agreements	31,461	(38,580)
Net increase (decrease) in short-term borrowings	6	(24)
Repayments of long-term debt	(12)	(10)
Redemption of preferred stock	0	(50,000)
Proceeds from issuance of common stock	2,476	3,145
Excess tax benefits from stock-based compensation	982	165
Purchase and retirement of common stock	(3,159)	(448)
Dividends paid to common stockholders	(7,036)	0
Net cash provided by (used in) financing activities	26,105	(297,818)
Net increase (decrease) in cash and cash equivalents	75,704	(302,789)
Cash and cash equivalents at beginning of period	534,827	801,332
Cash and cash equivalents at end of period	610,531	498,543
Supplemental disclosures of cash flow information:
Cash paid during the period for income taxes	0	3,376
Cash paid during the period for interest expense	$ 4,561	$ 5,859