Commitment and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended		6 Months Ended
	May 31, 2019	Mar. 31, 2018	Jun. 30, 2019	Jan. 31, 2019	Jan. 31, 2017
Commitments And Contingencies [Line Items]
Contractual obligation	$ 7,500,000
Contractual obligation completion month and year	2028-01	2021-12
Payment for amended arrangement			$ 47,000,000
Future obligation to purchase capital equipment	$ 50,000,000
Unemployment insurance assessment					$ 9,500,000
Minimum
Commitments And Contingencies [Line Items]
Contractual obligation		$ 150,000,000		$ 300,000,000
Purchase obligation, 2019				80,000
Purchase obligation, 2020				80,000
Purchase obligation, 2021				$ 80,000