Parent Company Financial Information SUMMARY STATEMENTS OF CASH FLOWS (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
Parent Company Financial Information
Net income	$ 8,065	$ 7,837	$ 7,825	$ 1,789	$ 3,891	$ 5,450	$ 4,643	$ 2,632	$ 25,515	$ 16,616	$ 8,993
Adjustments to reconcile net income to cash used in operating activities:
Share-based compensation expense									1,165	514	943
Increase (decrease) in accrued expenses and other liabilities									6,786	2,764	9,683
Net cash provided by operating activities									25,248	13,287	15,504
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of common stock, net of issuance cost									0	0	4,560
Repurchase of common stock									(116)	(5,638)	(59)
Proceeds from issuance of subordinated debentures									0	58,834	0
Net cash provided (used in) financing activities									275,103	222,938	(62,930)
Net increase (decrease) in cash and cash equivalents									(32,508)	(15,888)	67,461
Cash and cash equivalents, beginning of year				110,925				126,813	110,925	126,813	59,352
Cash and cash equivalents, end of year	78,417				110,925				78,417	110,925	126,813
Corporation
Parent Company Financial Information
Net income									25,515	16,616	8,993
Adjustments to reconcile net income to cash used in operating activities:
Share-based compensation expense									1,165	514	943
Equity in undistributed earnings of subsidiaries and dividends from the bank									(29,473)	(16,248)	(10,591)
Increase (decrease) in accrued expenses and other liabilities									166	1,560	(39)
Increase (decrease) in current and deferred taxes									3,566	(286)	1,153
Decrease (increase) in other assets									(6,893)	232	(504)
Net cash provided by operating activities									(5,954)	2,388	(45)
CASH FLOWS FROM FINANCING ACTIVITIES
Proceeds from issuance of common stock, net of issuance cost									0	0	4,560
Repurchase of common stock									(116)	(5,638)	(59)
Proceeds from exercise of options and warrants									758	267	90
Capital contribution to Bank									(10,000)	(40,000)	(8,700)
Proceeds from issuance of subordinated debentures									0	58,834	0
Net cash provided (used in) financing activities									(9,358)	13,463	(4,109)
Net increase (decrease) in cash and cash equivalents									(15,312)	15,851	(4,154)
Cash and cash equivalents, beginning of year				$ 18,724				$ 2,873	18,724	2,873	7,027
Cash and cash equivalents, end of year	$ 3,412				$ 18,724				$ 3,412	$ 18,724	$ 2,873