Stockholders' Equity - Additional Information (Detail) (USD $)	1 Months Ended	9 Months Ended		12 Months Ended
	Apr. 30, 2007	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2011
Stockholders Equity Note Disclosure [Line Items]
Common stock, shares reserved				3,893,210
Common stock, shares purchased through issuance of warrants	150,000
Common stock, shares purchased through issuance of warrants per share	$ 0.01
Warrant term	7 years
Stock-based compensation expense		$ 730,136	$ 748,235	$ 1,024,152		$ 1,003,266
Stock options outstanding		2,823,400	2,566,450	2,315,090
Closing price of the common stock				$ 6.28
Aggregate intrinsic value of stock options exercised		8,000	43,000	1,384,000	76,000
Weighted average grant date fair value of share-based awards granted		$ 1.89	$ 1.95	$ 3.62		$ 2.11
Total fair value of stock options vested		804,000	817,000	931,000		993,000
Total unrecognized compensation cost				$ 1,605,995
Unrecognized compensation cost, weighted average remaining requisite service period				2 years 9 months 4 days
Number of unvested options				739,009
2012 Plan
Stockholders Equity Note Disclosure [Line Items]
Number of shares available for future grant				1,578,120
Employee Stock Option | Minimum
Stockholders Equity Note Disclosure [Line Items]
Incentive options, vesting period				4 years
Incentive options, vesting on the first anniversary of the date of grant				20.00%
Employee Stock Option | Maximum
Stockholders Equity Note Disclosure [Line Items]
Incentive options, vesting period				5 years
Incentive options, vesting on the first anniversary of the date of grant				25.00%
Incentive options, term				10 years
Non-Employee Directors and Consultants
Stockholders Equity Note Disclosure [Line Items]
Incentive options, vesting period				1 year
Unvested Options
Stockholders Equity Note Disclosure [Line Items]
Incentive options, vesting period				5 years