Stockholders' Equity - Summary of Stock Option Activity (Detail)	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Shares, Outstanding, Beginning balance	1,257,000
Shares, Granted	0
Shares, Expired	(108,000)
Shares, Forfeited	(74,000)
Shares, Outstanding, Ending balance	1,075,000
Shares, Vested and expected to vest	1,055,000
Shares, Exercisable, Ending balance	943,000
Wtd. Avg. Exercise Price Outstanding, Beginning balance | $ / shares	$ 1.04
Wtd. Avg. Exercise Price, Expired | $ / shares	0.51
Wtd. Avg. Exercise Price, Forfeited | $ / shares	1.73
Wtd. Avg. Exercise Price, Outstanding, Ending balance | $ / shares	1.04
Wtd. Avg. Exercise Price, Vested and expected to vest | $ / shares	1.03
Wtd. Avg. Exercise Price, Exercisable, Ending balance | $ / shares	$ 0.97
Wtd. Avg. Remaining Contractual Life, Outstanding	3 years 9 months 26 days
Wtd. Avg. Remaining Contractual Life, Vested and expected to vest	3 years 9 months 11 days
Wtd. Avg. Remaining Contractual Life, Exercisable	3 years 6 months 11 days
Aggregate Intrinsic Value, Outstanding | $	$ 0