Basis of Presentation and Accounting Policies (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($) segment	Dec. 31, 2019 USD ($)	Jan. 01, 2019 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of operating segments | segment	1
Increase in accumulated deficit	$ 412,955	$ 1,852,978
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201602Member
Cumulative effect adjustment for adoption of new accounting guidance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Increase in accumulated deficit			$ 40,300