PARENT ONLY CONDENSED FINANCIAL STATEMENTS - Parent Only Condensed Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Expenses
Interest expense									$ 8,385	$ 8,607	$ 9,979
Salaries and benefits									57,741	54,132	52,165
Income before income tax									45,775	36,775	31,664
Income tax (benefit)									10,233	7,779	5,319
Net income	$ 9,108	$ 9,111	$ 9,660	$ 7,663	$ 6,560	$ 8,457	$ 7,754	$ 6,225	35,542	28,996	26,345
Parent Company
Income
Dividends from subsidiaries									28,900	24,275	34,200
Fees from subsidiaries									13,232	13,518	14,160
Other income									19	526	9
Total income									42,151	38,319	48,369
Expenses
Interest expense									1,264	1,286	1,675
Salaries and benefits									9,873	11,038	9,790
Professional fees									1,238	1,372	951
Other expenses									9,233	9,381	10,059
Total expenses									21,608	23,077	22,475
Income before income tax									20,543	15,242	25,894
Income tax (benefit)									(2,989)	(3,118)	(2,849)
Income before equity in undistributed income of subsidiaries									23,532	18,360	28,743
Equity in undistributed income (loss) of subsidiaries									12,010	10,636	(2,398)
Net income									$ 35,542	$ 28,996	$ 26,345