Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Inventory reserve	$ 271	$ 992
Other reserves and allowances	7,870	3,470
Income tax basis in excess of financial statement basis in intangible assets	509	1,085
Deductible stock-based compensation	2,829	3,257
ASC 842 lease liability	8,989
Net operating loss carryforward	17,100	19,409
Tax credit carryforwards	402	500
Deferred tax assets	37,970	28,713
Valuation allowance	(13,809)	(13,946)
Net deferred tax assets	24,161	14,767
Deferred tax liabilities:
Prepaid & other expenses	(184)	(284)
Fixed assets	(3,735)	(4,826)
Intangible assets	(17,762)	(16,067)
ASC 842 right of use asset	(8,351)
Deferred tax liabilities	(30,032)	(21,177)
Net deferred tax liability	$ (5,871)	$ (6,410)