Consolidated Statements of Cash Flows (Unaudited) (USD $)	6 Months Ended		12 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Dec. 31, 2012
OPERATING ACTIVITIES
Net income	$ 12,513,000	$ 12,891,000	$ 14,793,000
Items not requiring (providing) cash:
Depreciation and amortization	2,940,000	2,751,000
Provision for loan losses	1,953,000	1,546,000
Net amortization (accretion) of investment securities and assets not covered by FDIC loss share	873,000	(138,000)
Stock-based compensation expense	714,000	769,000
Net accretion on assets covered by FDIC loss share	(3,170,000)	(1,494,000)
Deferred income taxes	(1,756,000)	(802,000)
Loss on sale of investments	193,000
Bank owned life insurance income	(644,000)	(723,000)
Changes in:
Interest receivable	1,893,000	2,151,000
Mortgage loans held for sale	10,913,000	7,481,000
Assets held in trading accounts	(2,515,000)	(271,000)
Other assets	4,997,000	2,014,000
Accrued expenses and other liabilities	(2,788,000)	1,816,000
Income taxes payable	158,000	897,000
Net cash provided by operating activities	26,274,000	28,888,000
INVESTING ACTIVITIES
Net originations of loans	(14,323,000)	(41,648,000)
Net collections of loans covered by FDIC loss share	53,044,000	43,343,000
Purchases of premises and equipment, net	(3,274,000)	(1,288,000)
Proceeds from sale of foreclosed assets held for sale	12,669,000	7,875,000
Proceeds from sale of foreclosed assets held for sale, covered by FDIC loss share	7,897,000	2,364,000
Proceeds from sale of available-for-sale securities	617,000	730,000
Proceeds from maturities of available-for-sale securities	69,930,000	153,832,000
Purchases of available-for-sale securities	(60,817,000)	(149,254,000)
Proceeds from maturities of held-to-maturity securities	105,426,000	310,755,000
Purchases of held-to-maturity securities	(164,840,000)	(310,695,000)
Purchase of bank owned life insurance	(7,000,000)	(25,000)
Cash received on FDIC loss share	8,447,000	9,682,000
Net cash provided by investing activities	7,776,000	25,671,000
FINANCING ACTIVITIES
Net change in deposits	(61,044,000)	(21,113,000)
Dividends paid	(6,903,000)	(6,838,000)
Net change in other borrowed funds	(11,782,000)	696,000
Net change in federal funds purchased and securities sold under agreements to repurchase	(25,015,000)	(44,546,000)
Net shares issued under stock compensation plans	450,000	324,000
Repurchase of common stock	(8,319,000)	(7,706,000)
Net cash used in financing activities	(112,613,000)	(79,183,000)
DECREASE IN CASH AND CASH EQUIVALENTS	(78,563,000)	(24,624,000)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	537,797,000	570,206,000	570,206,000
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 459,234,000	$ 545,582,000	$ 537,797,000