Significant Customers and Concentrations of Risk - Summary of Significant Customers Comprising 10% or More of Total Revenue (Detail) - USD ($)		3 Months Ended			6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015		Jun. 30, 2016	Jun. 30, 2015
Concentration Risk [Line Items]
Total revenues		$ 12,228,390	$ 14,420,391		$ 24,547,162	$ 22,768,428
Teva [Member]
Concentration Risk [Line Items]
Total revenues		6,505,126	4,796,402		12,990,976	7,129,217
McKesson [Member]
Concentration Risk [Line Items]
Total revenues	[1]	1,846,255	1,435,196		3,555,549	3,334,901
Ferring [Member]
Concentration Risk [Line Items]
Total revenues		1,055,767	828,651		2,714,389	2,300,067
AmerisourceBergen [Member]
Concentration Risk [Line Items]
Total revenues	[1]	1,354,801	1,393,527		2,501,887	2,268,672
LEO Pharma [Member]
Concentration Risk [Line Items]
Total revenues		$ 0	$ 5,142,857	[2]	$ 0	$ 6,000,000	[2]

[1] Represents estimated revenue based on OTREXUP™ shipments, a portion of which has not been recognized as revenue but is recorded in deferred revenue at the end of each period as discussed in Note 2 to the Consolidated Financial Statements.

[2] The licensing agreement with LEO Pharma A/S was terminated effective June 23, 2015 and accordingly no revenue was recognized or received from this customer for the three and six months ended June 30, 2016.