Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred tax assets:
Net operating loss carryforwards	$ 115,739	$ 104,785
Reserves and accruals	3,473	5,242
Depreciation and amortization	1,931	2,819
Tax credit carryforwards	20,480	18,268
Stock-based compensation	2,871	3,168
Right-of-use lease liability	9,322	9,451
Total gross deferred tax assets	153,816	143,733
Valuation allowance on deferred tax assets	(141,087)	(131,232)
Total deferred tax assets, net of valuation allowance	12,729	12,501
Deferred tax liabilities:
Fixed assets and intangibles	(8,416)	(12,272)
Right-of-use asset	(8,459)	(8,694)
Total deferred tax liabilities	(16,875)	(20,966)
Net deferred tax liability	(4,146)	(8,465)
Deferred tax liability per balance sheet	(4,329)	(8,697)
less deferred tax assets included in other long-term assets	$ 183	$ 232