Net Income Per Share - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share, Basic [Abstract]
Net income	$ 2,001	$ 1,599	$ 1,996	$ (1,663)	$ 3,393	$ 3,539	$ 5,903	$ 5,508	$ 3,933	$ 18,343	$ 32,920
Less: Net income attributable to participating securities									(38)	(373)	(499)
Net income attributable to common stockholders									$ 3,895	$ 17,970	$ 32,421
Weighted average shares outstanding used in basic per common share computations (in shares)									13,255	11,083	11,026
Basic EPS (in dollars per share)	$ 0.15	$ 0.12	$ 0.15	$ (0.13)	$ 0.30	$ 0.31	$ 0.52	$ 0.49	$ 0.29	$ 1.62	$ 2.94
Diluted EPS
Net income attributable to common stockholders									$ 3,895	$ 17,970	$ 32,421
Reallocation of net income attributable to participating securities									0	0	0
Net income attributable to common stockholders for diluted EPS									$ 3,895	$ 17,970	$ 32,421
Weighted average shares outstanding used in basic per common share computations (in shares)									13,255	11,083	11,026
Weighted average effect of dilutive securities: Performance share awards (in shares)									0	0	0
Weighted average shares outstanding used in diluted per common share computations (in shares)									13,255	11,083	11,026
Diluted EPS (in dollars per share)	$ 0.15	$ 0.12	$ 0.15	$ (0.13)	$ 0.30	$ 0.31	$ 0.52	$ 0.49	$ 0.29	$ 1.62	$ 2.94