Summary of Significant Accounting Policies - Calculation of Basic and Diluted Income (Loss) Per Common Share and Common Share Equivalents (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
Basic net income (loss) per common share
Net income (loss)	$ 9,614	$ 248	$ (2,268)	$ (1,643)	$ (976)	$ 368	$ (906)	$ 18	$ 5,951	$ (1,496)	$ 4,656
Less: Preferred stock dividends									(28)	(28)	(28)
Net income (loss) applicable to common stock									$ 5,923	$ (1,524)	$ 4,628
Basic weighted average number of common shares outstanding									10,795	10,774	10,992
Basic net income (loss) per common share	$ 0.89	$ 0.02	$ (0.21)	$ (0.15)	$ (0.09)	$ 0.03	$ (0.08)		$ 0.55	$ (0.14)	$ 0.42
Diluted net income (loss) per common share
Net income (loss) applicable to common stock									$ 5,923	$ (1,524)	$ 4,628
Add: Preferred stock dividends									28	28	28
Less: Fair value of stock warrants for dilutive warrants											(379)
Net income (loss) applicable to dilutive common stock									$ 5,951	$ (1,524)	$ 4,277
Basic weighted average number of common shares outstanding									10,795	10,774	10,992
Effect of dilutive securities
Dilutive preferred share conversions									83
Dilutive stock awards									13		15
Weighted average number of diluted shares outstanding adjustment									96		15
Diluted weighted average number of common shares outstanding									10,891	10,774	11,007
Diluted net income (loss) per common share	$ 0.88	$ 0.02	$ (0.21)	$ (0.15)	$ (0.09)	$ 0.03	$ (0.08)		$ 0.55	$ (0.14)	$ 0.39