Note Payable - Additional Information (Detail) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended
	Mar. 31, 2015	Dec. 31, 2014	Jul. 05, 2013
Debt [Line Items]
Term of loan	36 months
Interest rate		8.45%
LIBOR floor rate		0.50%
Interest rate at period end	8.95%	8.95%
Final payment fee rate	3.50%
Closing fee	0.50%
Exit fee percentage recorded as deferred loan costs	3.50%
Loan amount prepaid in each year thereafter	3.00%
Amortization Period of Discount	3 years
Mid Cap [Member]
Debt [Line Items]
Secured loan facility			$ 20,000,000
Net proceeds in aggregate amount			19,800,000
Secured loan facility due to Midcap	10,256,000
Unamortized discount net	(411,000)