Basis of Presentation and Summary of Significant Accounting Policies - Supplemental Schedule of Noncash Investing and Financing Activities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018		Dec. 31, 2017
Supplemental Schedule of Non-Cash Investing and Financing Activities
Accrued purchases of property, equipment, and software	$ 15,206	$ 1,141		$ 2,195
Series A preferred stock conversion	0	100,000		0
Series A preferred stock accretion, net	0	17,567		3,532
Vendor financed insurance premiums	$ 0	0		1,450
Convertible preferred stock accretion of beneficial conversion feature		17,567	[1]	$ 3,532
Acquired value of beneficial conversion feature		$ 6,100

[1] Represents total accretion of $17.6 million, net of $6.1 million acquired value of beneficial conversion feature attributable to repurchased Series A Convertible Preferred Stock.