REVISION OF PRIOR PERIOD FINANCIAL STATEMENTS (Details) (USD $)	3 Months Ended								12 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	Jan. 02, 2010 Understatement (Overstatement) of lease agreements with contractual cost escalators Restatement adjustment	Dec. 31, 2011 Understatement (Overstatement) of lease agreements with contractual cost escalators As Previously Reported	Dec. 31, 2010 Understatement (Overstatement) of lease agreements with contractual cost escalators As Previously Reported
Consolidated statements of operations information:
Non-interest expense	$ 44,266,000	$ 32,162,000	$ 34,184,000	$ 30,194,000	$ 29,530,000	$ 34,710,000	$ 28,623,000	$ 23,189,000	$ 140,806,000	$ 116,442,000	$ 82,137,000		$ 116,052,000	$ 81,729,000
Income from continuing operations before income taxes	12,512,000	14,876,000	10,907,000	8,753,000	8,167,000	4,802,000	2,248,000	3,491,000	47,048,000	18,318,000	16,035,000		18,708,000	16,443,000
Income tax expense	3,183,000	4,847,000	2,921,000	2,272,000	609,000	405,000	371,000	656,000	13,223,000	1,884,000	2,420,000		2,041,000	2,585,000
Net income from continuing operations	9,329,000	10,029,000	7,986,000	6,481,000	7,558,000	4,397,000	1,877,000	2,835,000	33,825,000	16,434,000	13,615,000		16,667,000	13,858,000
Net income (loss) available to common stockholders	9,329,000	10,029,000	7,986,000	5,844,000	8,477,000	4,392,000	1,877,000	2,835,000	33,188,000	17,348,000	13,615,000		17,581,000	13,858,000
Basic earnings per share (in dollars per share)	$ 0.39	$ 0.46	$ 0.37	$ 0.28	$ 0.40	$ 0.22	$ 0.11	$ 0.20		$ 0.97	$ 0.98		$ 0.98	$ 1.00
Diluted earnings per share (in dollars per share)	$ 0.38	$ 0.46	$ 0.37	$ 0.28	$ 0.40	$ 0.22	$ 0.11	$ 0.20		$ 0.97	$ 0.98		$ 0.98	$ 1.00
Consolidated balance sheets information:
Deferred tax assets, net	57,729,000				40,744,000				57,729,000	40,744,000	18,674,000		39,691,000	17,779,000
Other liabilities	81,047,000				46,368,000				81,047,000	46,368,000	30,233,000		43,758,000	28,014,000
Retained earnings	$ 122,014,000				$ 107,920,000				$ 122,014,000	$ 107,920,000	$ 102,648,000	$ (1,100,000)	$ 109,477,000	$ 103,972,000