Debt Obligations - Narrative (Details)					12 Months Ended
	Jan. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) installment	Jun. 30, 2017 USD ($)	Dec. 15, 2016 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) installment	Jun. 30, 2020 USD ($)	Apr. 21, 2017 USD ($)	Jul. 29, 2016 USD ($)
Debt Instrument [Line Items]
Proceeds from credit facility					$ 1,143,700,000	$ 1,142,717,000	$ 1,823,207,000
Loss on early extinguishment of debt					0	6,375,000	18,375,000
Maximum borrowing capacity					175,000,000	225,000,000		$ 200,000,000
Proceeds from senior debt					0	193,625,000	381,625,000
Long term debt					528,403,000	714,392,000
Payments to extinguish original term facility							198,973,000
Payments to extinguish related party portion of original term facility							155,368,000
Interest expense, related party					17,002,000	24,770,000	28,846,000
Debt issuance costs, line of credit arrangements, net					2,500,000	3,500,000
Senior Term Loan, related party, net | Senior Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 825,000,000.0					$ 825,000,000.0
Number of installments | installment		2					2
Proceeds from senior debt	$ 425,000,000.0	$ 400,000,000.0
Long term debt	825,000,000.0				449,165,000	609,407,000
Proceeds from debt, net	418,600,000						$ 381,600,000
Debt issuance costs	6,400,000	18,400,000					18,400,000
Interest costs capitalized							700,000
Interest expense, related party					17,000,000.0	24,800,000	28,800,000
Accrued interest					$ 8,500,000	$ 13,200,000
Debt instrument, covenant, leverage ratio to EBITDA, maximum					3.5
Senior Term Loan, related party, net | Senior Notes | LIBOR +
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					9.00%
Senior Term Loan, related party, net | Senior Notes | Affiliated Entity
Debt Instrument [Line Items]
Line of credit, percent of ownership					25.20%	31.10%
Long term debt	$ 250,000,000.0
Senior Term Loan, related party, net | Senior Notes | Affiliated Entity | Mudrick Capital Management
Debt Instrument [Line Items]
Line of credit, percent of ownership					4.00%	3.20%
Senior Term Loan, related party, net | Senior Notes | Affiliated Entity | Paulson and Co
Debt Instrument [Line Items]
Line of credit, percent of ownership						9.10%
Senior Term Loan, related party, net | Senior Notes | Affiliated Entity | GoldenTree Asset Management
Debt Instrument [Line Items]
Line of credit, percent of ownership					21.20%	18.80%
Revolving Credit Facility | ABL Facility | Line of Credit
Debt Instrument [Line Items]
Maximum borrowing capacity			$ 350,000,000.0	$ 150,000,000.0					$ 200,000,000.0
Long term debt					$ 79,238,000	$ 104,985,000
Debt issuance costs			3,900,000	$ 2,100,000
Debt issuance costs, line of credit arrangements, gross			700,000
Line of credit, percent of commitments outstanding				75.00%
Current borrowing capacity					$ 57,600,000
Debt instrument, covenant, fixed charge coverage ratio required, minimum					1.00
Debt instrument, covenant, remaining borrowing capacity required, minimum					$ 14,000,000
Revolving Credit Facility | ABL Facility | Line of Credit | LIBOR +
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				4.00%	4.00%
Original Term Facility
Debt Instrument [Line Items]
Loss on early extinguishment of debt						$ 6,400,000	18,400,000
Original Term Facility | Line of Credit
Debt Instrument [Line Items]
Long-term line of credit		$ 354,300,000					354,300,000			$ 600,000,000.0
Proceeds from credit facility			$ 550,000,000.0
Original Term Facility | Line of Credit | Affiliated Entity
Debt Instrument [Line Items]
Line of credit, percent of ownership			49.40%
Payments to extinguish original term facility							354,300,000
Payments to extinguish related party portion of original term facility							$ 155,400,000
Equity, percent ownership		85.70%					85.70%
Original Term Facility | Line of Credit | Affiliated Entity | Mudrick Capital Management
Debt Instrument [Line Items]
Line of credit, percent of ownership			16.90%
Original Term Facility | Line of Credit | Affiliated Entity | Paulson and Co
Debt Instrument [Line Items]
Line of credit, percent of ownership			16.40%
Original Term Facility | Line of Credit | Affiliated Entity | GoldenTree Asset Management
Debt Instrument [Line Items]
Line of credit, percent of ownership			16.10%