Accounts Payable and Accrued Liabilities - Summary of Components of Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accounts payable	$ 12,381	$ 9,397
Accrued price adjustments	1,420	592
Accrued returns	760
Accrued acquisition consideration	7,536
Accrued rebates	4,228	3,842
Accrued chargebacks	52	10
Accrued compensation and benefits	1,574	2,052
Accrued royalties	586	518
Accrued clinical trial costs	397	615
Accrued legal costs	1,109	490
Accrued manufacturing costs	200	200
Accrued sales and marketing costs		193
Accrued other	278	265
Total accounts payable and accrued expenses	$ 30,521	$ 18,174