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Debt - Narrative (Details) - USD ($)		1 Months Ended	6 Months Ended
Debt - Narrative (Details) - USD ($)	Mar. 24, 2020	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Mar. 01, 2018	Nov. 02, 2017
Debt Instrument [Line Items]
Borrowings under ABL Facility			$ 0	$ 70,000,000
Outstanding debt			380,292,000		$ 379,908,000
Cash and cash equivalents			266,876,000		$ 211,916,000
Senior Secured Notes \| Senior Secured Notes Due 2024, Existing Notes
Debt Instrument [Line Items]
Face amount of debt							$ 350,000,000.0
Stated interest rate (as a percent)							8.00%
Senior Secured Notes \| Senior Secured Notes Due 2024, New Notes
Debt Instrument [Line Items]
Face amount of debt						$ 125,000,000.0
Senior Secured Notes \| Senior Secured Notes Due 2024, Existing Notes, Restricted Payment Offer
Debt Instrument [Line Items]
Stated interest rate (as a percent)						8.00%
ABL Borrowings \| ABL Facility
Debt Instrument [Line Items]
Amount of borrowings available			21,000,000.0
Citibank \| ABL Borrowings
Debt Instrument [Line Items]
Borrowings under ABL Facility	$ 70,000,000.0
Repayment of debt		$ 30,000,000.0
Outstanding debt			$ 40,000,000.0