Long-Term Debt - Senior Notes (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Nov. 06, 2018
Debt Instrument [Line Items]
Long-term debt	$ 589,294,000	$ 537,926,000
Senior Notes \| 6.125% Senior Notes
Debt Instrument [Line Items]
Stated interest rate			6.125%
Debt instrument face amount			$ 550,000,000.0
Issued price percentage			98.937%
Yield percentage			6.375%
Long-term debt	540,377,000	537,926,000
Debt issuance costs	5,000,000.0	6,600,000
Debt discount	4,700,000	5,800,000
Amortization of debt issuance costs	1,300,000	200,000
Amortization of debt issuance discounts	1,000,000.0	200,000
Interest expense	$ 34,700,000	$ 5,500,000

Issued price percentage.

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Yield percentage.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Amount of amortization expense attributable to debt issuance costs.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after accumulated amortization, of debt discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Aggregate amount of interest paid or due on all long-term debt.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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