Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
OPERATING ACTIVITIES
Net income	$ 19,651,000	$ 19,069,000
Items not requiring (providing) cash
Depreciation and amortization	4,116,000	4,542,000
Provision for loan losses	2,846,000	8,845,000
Net accretion of investment securities	(112,000)	(9,000)
Stock-based compensation expense	1,065,043	920,919
Net accretion on assets covered by FDIC loss share	(1,912,000)	(3,575,000)
Gain on FDIC-assisted transactions	(1,120,000)
Deferred income taxes	86,000	(2,490,000)
Bank owned life insurance income	(1,078,000)	(1,078,000)
Changes in
Interest receivable	(127,000)	1,168,000
Mortgage loans held for sale	(1,004,000)	(3,800,000)
Assets held in trading accounts	539,000	2,325,000
Other assets	(2,143,000)	1,922,000
Accrued interest and other liabilities	5,750,000	(2,428,000)
Income taxes payable	(2,575,000)	(1,271,000)
Net cash provided by operating activities	23,982,000	24,141,000
INVESTING ACTIVITIES
Net (originations) collections of loans	(52,392,000)	27,386,000
Net collections of loans covered by FDIC loss share	51,922,000	51,625,000
Purchases of premises and equipment, net	(1,988,000)	(13,645,000)
Proceeds from sale of foreclosed assets held for sale	5,296,000	19,472,000
Proceeds from sale of foreclosed assets held for sale, covered by FDIC loss share	10,000,000	5,241,000
Proceeds from sale of available-for-sale securities	813,000	5,331,000
Proceeds from maturities of available-for-sale securities	236,921,000	255,255,000
Purchases of available-for-sale securities	(246,929,000)	(252,556,000)
Proceeds from maturities of held-to-maturity securities	512,920,000	132,733,000
Purchases of held-to-maturity securities	(497,955,000)	(171,855,000)
Purchase of bank owned life insurance	(25,000)	(25,000)
Net cash proceeds received in FDIC-assisted transactions	44,015,000
Cash received on FDIC loss share	12,553,000	25,531,000
Net cash provided by investing activities	75,151,000	84,493,000
FINANCING ACTIVITIES
Net change in deposits	(83,655,000)	26,045,000
Dividends paid	(10,172,000)	(9,885,000)
Net change in other borrowed funds	(1,318,000)	(42,375,000)
Net change in federal funds purchased and securities sold under agreements to repurchase	(71,393,000)	(10,853,000)
Net shares issued under stock compensation plans	324,000	474,000
Repurchase of common stock	(14,674,000)	(409,000)
Net cash used in financing activities	(180,888,000)	(37,003,000)
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(81,755,000)	71,631,000
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	570,206,000	452,060,000
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 488,451,000	$ 523,691,000