Debt - Narrative (Details) - USD ($)		12 Months Ended
	Jul. 31, 2015	Dec. 31, 2019	Dec. 31, 2018	Jan. 31, 2019	Jan. 30, 2019
Line of Credit Facility [Line Items]
Outstanding loan balance		$ 406,625,000
Accretion of debt issuance costs		$ 2,500,000	$ 2,500,000
Excess cash flows, repayment of debt, percentage		50.00%
Excess cash flows threshold for dividend		$ 5,000,000
Repayments of principal in next 12 months		4,675,000
Term Loan
Line of Credit Facility [Line Items]
Debt issuance costs incurred	$ 12,900,000	12,900,000
Debt issuance costs, net		3,886,000	6,168,000
Face amount	$ 425,000,000.0	425,000,000.0
Amortization per year (as a percent)	1.00%
Maximum borrowing available				$ 12,500,000	$ 25,000,000.0
Outstanding loan balance		405,900,000
Revolving loan
Line of Credit Facility [Line Items]
Debt issuance costs incurred	$ 1,300,000
Face amount		25,000,000.0
Maximum borrowing available				$ 12,500,000
Outstanding loan balance		0
Letter-of-credit sub-facility
Line of Credit Facility [Line Items]
Face amount		10,000,000.0
Maximum borrowing available	$ 10,000,000
Letters of credit issued, amount		30,000.00
Credit facility amount outstanding		0
Credit Facility
Line of Credit Facility [Line Items]
Repayments of principal in next 12 months		4,700,000
Credit Facility | Alternate base rate
Line of Credit Facility [Line Items]
Margin of interest (as a percent)	3.75%
Credit Facility | LIBOR
Line of Credit Facility [Line Items]
Margin of interest (as a percent)	4.75%
Variable rate base minimum (as a percent)	1.00%
Level 2 | Term Loan
Line of Credit Facility [Line Items]
Fair value of long-term debt		345,000,000.0	$ 397,100,000
Level 2 | Recurring | Interest rate swap | Derivative Financial Instruments, Liabilities
Line of Credit Facility [Line Items]
Fair value of the liability		(100,000)
Prepayment due to excess cash flow provision | Term Loan
Line of Credit Facility [Line Items]
Repayments of principal in next 12 months		$ 0