Unaudited Supplementary Quarterly Financial Information - Unaudited Supplementary Quarterly Financial Information (Detail) (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
Quarterly Financial Information Disclosure [Abstract]
Total revenue	$ 26,781	$ 25,399	$ 27,900	$ 23,476	$ 24,248	$ 24,165	$ 27,187	$ 25,281	$ 103,556	$ 100,881	$ 102,443
Gross profit	10,734	9,657	10,041	7,140	8,442	8,812	9,460	8,565	37,572	35,279	38,697
Net (loss) income	$ 32,411	$ 1,772	$ 1,414	$ (889)	$ 345	$ 793	$ 134	$ 175	$ 34,708	$ 1,447	$ 344
Basic (loss) income per share	$ 2.99	$ 0.17	$ 0.13	$ (0.08)	$ 0.03	$ 0.07	$ 0.01	$ 0.02	$ 3.21	$ 0.13	$ 0.03
Diluted (loss) income per share	$ 2.55	$ 0.14	$ 0.12	$ (0.08)	$ 0.03	$ 0.07	$ 0.01	$ 0.02	$ 2.88	$ 0.13	$ 0.03