Loan Facilities - Additional Information (Details) - USD ($)			3 Months Ended		9 Months Ended	12 Months Ended	45 Months Ended
	Mar. 31, 2018	Oct. 12, 2017	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2017	Dec. 31, 2018	Sep. 30, 2022	Dec. 31, 2017
Line of Credit Facility [Line Items]
Secured loan payable	$ 335,250,000		$ 335,250,000					$ 339,048,000
Interest expense			5,261,000	$ 819,000	$ 5,300,000
Recapitalization Credit Agreement | Secured Debt
Line of Credit Facility [Line Items]
Unamortized discount (premium) and debt issuance costs, net		$ 11,500,000
Unamortized discount		1,750,000
Deferred financing costs		9,800,000
Amortization of debt issuance costs and discounts			$ 600,000
Recapitalization Credit Agreement | Secured Debt | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)			2.75%
Recapitalization Credit Agreement | Secured Debt | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate (percent)			3.75%
Revolving Credit Facility | Secured Debt
Line of Credit Facility [Line Items]
Covenant, leverage ratio, excess borrowings, minimum			$ 12,500,000
Revolving Credit Facility | Recapitalization Credit Agreement | Secured Debt
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity		$ 20,000,000
Debt instrument term (years)		3 years
Secured loan payable	0		$ 0					0
Term Loan | Secured Debt
Line of Credit Facility [Line Items]
Capital stock Of subsidiary, percentage			100.00%
Term Loan | Recapitalization Credit Agreement | Secured Debt
Line of Credit Facility [Line Items]
Line of credit, maximum borrowing capacity		$ 350,000,000
Debt instrument term (years)		5 years
Secured loan payable	335,300,000		$ 335,300,000					$ 339,000,000
Quarterly payment of principal	$ 4,375,000
Term Loan | Term Loan Facility [Member] | Secured Debt
Line of Credit Facility [Line Items]
Long-term debt, weighted average interest rate, over time (percent)			5.35%
Scenario, Forecast | Term Loan | Recapitalization Credit Agreement | Secured Debt
Line of Credit Facility [Line Items]
Quarterly payment of principal							$ 8,750,000
Annual principal payment							$ 35,000,000
Annual prepayment of principal, period of time required before year end						90 days
Annual principal payment, percentage of excess cash flow						50.00%
Prepaid, Refinanced, or Repriced Prior to April 12, 2019 | Term Loan | Recapitalization Credit Agreement | Secured Debt
Line of Credit Facility [Line Items]
Debt instrument, redemption price, percentage			101.00%
Non-US [Member] | Term Loan | Secured Debt
Line of Credit Facility [Line Items]
Capital stock Of subsidiary, percentage			65.00%