Quarterly Results of Operations (Unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2015	[1]	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
Effect of Fourth Quarter Events [Line Items]
Interest income	$ 29,983		$ 23,056	$ 23,657	$ 22,451	$ 22,292	$ 22,417	$ 22,284	$ 21,392	$ 99,144	$ 88,385	$ 88,183
Interest expense	3,612		3,044	3,022	3,014	3,056	3,048	3,041	2,983	12,692	12,128	12,742
Net interest income	26,371		20,012	20,635	19,437	19,236	19,369	19,243	18,409	86,452	76,257	75,441
Provision for credit losses	957		279	254	446	545	539	643	493	1,936	2,220	2,028
Non-interest income	8,464		6,561	6,310	6,144	6,221	5,954	6,509	5,686	27,482	24,370	27,835
Non-interest expense	31,470		16,711	16,157	16,801	16,301	15,179	15,792	15,125	81,139	62,397	66,333
Income before income tax	2,408		9,583	10,534	8,334	8,611	9,605	9,317	8,477	30,859	36,010	34,915
Income tax expense	716		3,127	3,341	2,723	2,523	3,154	3,001	2,762	9,907	11,440	12,132
Net income	$ 1,692		$ 6,456	$ 7,193	$ 5,611	$ 6,088	$ 6,451	$ 6,316	$ 5,715	$ 20,952	$ 24,570	$ 22,783
Per common share:
Basic earnings per share	$ 0.17		$ 0.86	$ 0.97	$ 0.75	$ 0.82	$ 0.87	$ 0.85	$ 0.76	$ 2.60	$ 3.29	$ 2.98
Diluted earnings per share	$ 0.17		$ 0.86	$ 0.96	$ 0.75	$ 0.82	$ 0.86	$ 0.85	$ 0.75	$ 2.60	$ 3.28	$ 2.97
Common Stock [Member]
Effect of Fourth Quarter Events [Line Items]
Stock Issued During Period, Shares, Acquisitions										2,749,762

[1] On October 16, 2015, the Company completed its acquisition of SBM. Fourth quarter 2015 results of operations include revenues and expenses incurred as a combined organization from the acquisition date through December 31, 2015. The decrease in basic and diluted EPS in the fourth quarter of 2015 was due to acquisition costs and the issuance of 2.7 million shares of Company common stock in connection with the acquisition. Refer to Note 2 and 3 for additional details of the acquisition