PARENT ONLY CONDENSED FINANCIAL STATEMENTS (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Operating Activities
Net income	$ 7,279	$ 6,986	$ 6,982	$ 6,011	$ 6,026	$ 5,615	$ 7,626	$ 4,546	$ 27,258	$ 23,813	$ 14,802
Change in other assets and liabilities									1,928	3,734	6,940
Net cash provided by operating activities									54,191	36,060	62,634
Investing Activities
Purchase of security AFS									(220,543)	(527,834)	(363,844)
Purchases of equipment									(7,387)	(6,865)	(4,660)
Net cash provided (used) by investing activities									(39,297)	76,316	73,191
Financing Activities
Proceeds from exercise of stock options									120
Repurchase of preferred shares									(40,255)
Cash dividends on preferred stock									(1,967)	(2,850)	(2,850)
Cash dividends on common stock									(1,623)	(807)	(805)
Net cash (used) by financing activities									(58,392)	(63,351)	(147,391)
Net change in cash and cash equivalents									(43,498)	49,025	(11,566)
Cash and cash equivalents, beginning of year				109,148				60,123	109,148	60,123	71,689
Cash and cash equivalents, end of year	65,650				109,148				65,650	109,148	60,123
Parent Company
Operating Activities
Net income									27,258	23,813	14,802
Undistributed (income)/loss of subsidiaries									13,915	(26,951)	(19,107)
Change in other assets and liabilities									2,862	2,699	1,838
Net cash provided by operating activities									44,035	(439)	(2,467)
Investing Activities
Cash received from subsidiaries											1,287
Purchase of security AFS											(39)
Purchases of equipment									(1,230)	(2,166)	(1,766)
Net cash provided (used) by investing activities									(1,230)	(2,166)	(518)
Financing Activities
Proceeds from exercise of stock options									120
Repurchase of preferred shares									(40,255)
Cash dividends on preferred stock									(1,967)	(2,850)	(2,850)
Cash dividends on common stock									(1,623)	(807)	(805)
Net cash (used) by financing activities									(43,725)	(3,657)	(3,655)
Net change in cash and cash equivalents									(920)	(6,262)	(6,640)
Cash and cash equivalents, beginning of year				8,022				14,284	8,022	14,284	20,924
Cash and cash equivalents, end of year	$ 7,102				$ 8,022				$ 7,102	$ 8,022	$ 14,284