Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)	Jan. 01, 2020 USD ($)	Dec. 31, 2019 USD ($)
Accounting Policies [Abstract]
Comprehensive loss	$ 23,041	$ 20,283
Restricted cash	$ 1,500			$ 1,500
Number of operating segments | segment	1
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets	$ 12,106
Operating lease liability	$ 13,257
Accounting Standards Update 2016-02
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right-of-use assets			$ 12,700
Operating lease liability			$ 13,900