Consolidated Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2019

Balance Sheet Related Disclosures [Abstract]

Property, Plant and Equipment

Estimated useful lives for property and equipment are as follows:

Property and Equipment	Estimated Useful Life
Machinery and equipment	3 – 5 years
Furniture and fixtures	7 years
Computer hardware and computer software	3 years
Leasehold improvements	Lesser of estimated useful life or remaining lease term

Property and equipment, net consist of the following:

	As of December 31,
	2019			2018
	(in thousands)
Machinery and equipment	$	29,119		$	23,440
Computer hardware	6,296			4,949
Leasehold improvements	21,031			13,965
Furniture and fixtures	1,962			1,522
Computer software	829			643
Construction in progress	6,354			3,118
Property and equipment, gross	65,591			47,637
Less: accumulated depreciation and amortization	(21,923		)	(16,634		)
Property and equipment, net	$	43,668		$	31,003

Schedule of Accrued Liabilities

Accrued expenses consist of the following:

	As of December 31,
	2019		2018
	(in thousands)
Accrued royalty obligations	$	1,564	$	707
Accrued legal expenses	1,046		814
Accrued tax liabilities	3,050		1,470
Accrued professional services	3,464		1,791
Accrued clinical trials and studies	2,029		236
Purchases of property and equipment included in accrued expenses	2,424		343
Operating lease liabilities	7,140		—
Other	4,986		1,817
Total accrued expenses	$	25,703	$	7,178