Summary of Stock Option Activity (Detail) (USD $)	9 Months Ended
	Sep. 30, 2014
Number of Shares
Beginning Balance	279,000
Granted	8,000
Exercised	(140,000)
Forfeited	(28,000)
Ending Balance	119,000
Exercisable	111,000
Options vested and expected to vest thereafter	119,000
Weighted Average Exercise Price
Beginning Balance	$ 3.31
Granted	$ 3.30
Exercised	$ 1.13
Forfeited	$ 6.34
Ending Balance	$ 5.16
Exercisable	$ 5.29
Options vested and expected to vest thereafter	$ 5.16
Weighted-Average Remaining Contractual Term
Outstanding, end of period	4 years 2 months 12 days
Exercisable, end of period	3 years 8 months 12 days
Options vested and expected to vest thereafter	4 years 2 months 12 days
Aggregate Intrinsic Value
Outstanding, end of period	$ 22,000
Exercisable	22,000
Options vested and expected to vest thereafter	$ 22,000