Credit Facility and Capital Leases - Additional Information (Detail) (USD $)	0 Months Ended	3 Months Ended	9 Months Ended	3 Months Ended	0 Months Ended
	Jun. 30, 2013	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2014 Minimum	Jul. 05, 2012 Line of Credit	Sep. 30, 2014 Before July 5, 2013	Jun. 18, 2013 Before July 5, 2013	Sep. 30, 2014 After July 5, 2013	Sep. 30, 2014 Letter Of Credit Sublimit	May 05, 2014 Revolving Credit Facility	May 04, 2014 Revolving Credit Facility
Line of Credit Facility [Line Items]
Credit agreement term					3 years
Line of credit facility maximum borrowing capacity						$ 25,000,000	$ 25,000,000	$ 30,000,000	$ 2,000,000	$ 10,000,000	$ 25,000,000
Commitment fee	0.30%
Outstanding balance of revolving credit facility			$ 575,000
Interest rate			0.50%
LIBOR rate			2.00%
Revolving credit facility, maturity date			Jul. 05, 2015
Interest rate for borrowings under credit facility			2.20%
Underlying property and equipment expiration period				September 2019
Weighted-average imputed interest rates for the capital lease agreements		2.60%