Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accounts payable	$ 13,289	$ 11,704
Accrued rebates	28,553	28,528
Accrued compensation and benefits	4,557	5,545
Accrued returns	7,014	4,438
Accrued royalties	648	535
Accrued legal	1,049	1,484
Accrued regulatory expenses	819	331
Accrued other	717	1,428
Total accounts payable and accrued liabilities	$ 56,646	$ 53,993