Selected Quarterly Financial Data (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Selected Quarterly Financial Information [Abstract]
Interest income	$ 18,554	$ 18,469	$ 18,726	$ 19,610	$ 21,439	$ 22,262	$ 22,726	$ 23,283	$ 75,359	$ 89,710	$ 89,707
Interest expense	1,301	1,322	1,369	1,428	1,585	1,710	1,837	1,981	5,420	7,113	9,981
Net interest income	17,253	17,147	17,357	18,182	19,854	20,552	20,889	21,302	69,939	82,597	79,726
Provision for loan losses	376	525	11,764	1,950	3,746	1,250	2,748	2,000	1,875	7,100	10,500
Net interest income after provision for loan losses	16,877	16,622	5,593	16,232	16,108	19,302	18,141	19,302	55,324	72,853	69,676
Noninterest income	3,165	3,137	11,697	4,346	4,603	1,358	988	1,297	22,345	8,246	9,212
Noninterest expense	16,436	13,072	12,926	13,867	13,972	13,663	15,109	13,655	56,301	56,399	55,825
Income before provision for income tax	3,606	6,687	4,364	6,711	6,739	6,997	4,020	6,944	21,368	24,700	23,063
Provision for income tax	1,104	2,185	1,456	2,127	2,153	2,359	1,173	2,171	6,872	7,856	7,111
Net income available to common shareholders	$ 2,502	$ 4,502	$ 2,908	$ 4,584	$ 4,586	$ 4,638	$ 2,847	$ 4,773	$ 14,496	$ 16,844	$ 14,868
Basic (in dollars per share)	$ 0.16	$ 0.29	$ 0.19	$ 0.30	$ 0.30	$ 0.30	$ 0.18	$ 0.31	$ 0.94	$ 1.09	$ 0.97
Diluted (in dollars per share)	$ 0.16	$ 0.29	$ 0.19	$ 0.30	$ 0.30	$ 0.30	$ 0.18	$ 0.31	$ 0.93	$ 1.09	$ 0.97
Cash dividends declared per share (in dollars per share)	$ 0.14	$ 0.09	$ 0.15	$ 0.15	$ 0.15	$ 0.09	$ 0.14	$ 0.12	$ 0.54	$ 0.50	$ 0.20