Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred Tax Assets:
Net operating loss	$ 17,010	$ 14,350
Research and development and other tax credits	5,920	2,349
Share-based compensation	3,259	3,439
Interest limitation carryforward	2,992	839
Accrued expenses	2,918	3,759
Accrued settlement costs	2,464	3,276
Bad debts	2,138	4,859
Lease obligation	1,021	1,044
Sales return and allowances	170	659
Other	1,075	1,285
Deferred Tax Liabilities:
Prepaid expenses	(1,170)	(1,189)
Property and equipment	(1,073)	(1,582)
Right of use asset	(895)	(868)
Intangible assets	(160)	(389)
Deferred costs of goods sold	(43)	(322)
Unearned insurance refund	0	(894)
Net Deferred Tax Assets
Net Deferred Tax Assets	35,626	30,615
Less: Valuation allowance	(35,626)	(30,615)
Net Deferred Tax Assets after Valuation Allowance	$ 0	$ 0