Shareholders' Equity - Summary of Stock Option Activity (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Beginning Balance	1,515,621
Granted, Number of Shares	337,325
Exercised, Number of Shares	(254,152)
Forfeited, Number of Shares	(34,021)
Expired, Number of Shares	(239,371)
Number of Shares, Ending Balance	1,325,402
Vested and expected to vest, Number of Shares, Ending Balance	1,248,749
Exercisable, Number of Shares, Ending Balance	708,013
Weighted Average Exercise Price, Beginning Balance	$ 3.36
Granted, Weighted Average Exercise Price	$ 3.32
Exercised, Weighted Average Exercise Price	$ 2.43
Forfeited, Weighted Average Exercise Price	$ 3.13
Expired, Weighted Average Exercise Price	$ 4.47
Weighted Average Exercise Price, Ending Balance	$ 3.34
Vested and expected to vest, Weighted Average Exercise Price, Ending Balance	$ 3.34
Exercisable, Weighted Average Exercise Price, Ending Balance	$ 3.34
Weighted Average Remaining Contractual Life (in years)	5 years 9 months 15 days
Vested and expected to vest, Weighted Average Remaining Contractual Life (in years)	5 years 7 months 13 days
Exercisable, Weighted Average Remaining Contractual Life (in years)	3 years 6 months 18 days
Aggregate Intrinsic Value	$ 348,579
Vested and expected to vest, Aggregate Intrinsic Value	345,455
Exercisable, Aggregate Intrinsic Value	$ 310,236