Accounts Payable and Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accounts payable	$ 17,699	$ 11,704
Accrued rebates	29,172	28,528
Accrued compensation and benefits	3,768	5,545
Accrued returns	6,248	4,438
Accrued royalties	733	535
Accrued legal	1,554	1,484
Accrued regulatory expenses	547	331
Accrued other	1,210	1,428
Total accounts payable and accrued liabilities	$ 60,931	$ 53,993