Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Numerator:
Net income	$ 4,811	$ 4,474	$ 7,835	$ 6,605
Less: Net income allocated to unvested participating securities	89	68	145	100
Net income available to common stockholders	$ 4,722	$ 4,406	$ 7,690	$ 6,505
Denominator:
Denominator for basic earnings per share - weighted average shares	5,754	5,712	5,752	5,711
Effect of dilutive securities:
Common stock equivalents	9	45	9	48
Denominator for diluted earnings per share - adjusted weighted-average shares and assumed conversions	5,763	5,757	5,761	5,759
Basic earnings per share	$ 0.82	$ 0.77	$ 1.34	$ 1.14
Diluted earnings per share	$ 0.82	$ 0.77	$ 1.33	$ 1.13