Income Taxes - Schedule of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Deferred tax assets:
Net operating loss carryforwards	$ 711	$ 3,924
Intangible assets	3,502	2,935
Sale-leaseback, net	617	628
Allowance for returns and discounts	4,541	5,358
Stock-based compensation	5,333	5,933
Tax credit carryforwards	12,246	5,247
Other, net	6,883	4,580
Total deferred tax assets	33,833	28,605
Valuation allowance for deferred tax assets	(1,830)	(15,204)
Total deferred tax assets	32,003	13,401
Deferred tax liabilities:
Convertible Senior Notes	(636)	(3,633)
Intangible assets	(2,165)	(2,935)
Property, plant and equipment	(7,010)	(7,263)
Deferred Tax Liabilities, Gross	(9,811)	(13,831)
Total deferred tax liabilities		$ (430)
Deferred Tax Assets, Net	$ 22,192