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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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

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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The effective interest rate at the end of the reporting period.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Long-Term Debt - Components of Debt (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018	Dec. 19, 2018	Apr. 04, 2017	Nov. 19, 2013
Long-Term Debt
Long-term debt	$ 739,475,000	$ 818,485,000
Interest rate			5.125%
Aggregate principle amount			$ 250,000,000.0
Revolving Credit Facility
Long-Term Debt
Long-term debt	$ 167,227,000	$ 259,081,000
Weighted average interest rate	2.30%	2.80%
Convertible Notes
Long-Term Debt
Long-term debt	$ 275,703,000	$ 263,507,000
Interest rate	1.00%	1.00%			1.00%
Aggregate principle amount	$ 287,500,000				$ 287,500,000
Unamortized discount and capitalized debt issuance costs	11,797,000	$ 23,993,000
Senior Notes 5.50 Percent Due 2025
Long-Term Debt
Long-term debt	$ 296,545,000	$ 295,897,000
Interest rate	5.50%	5.50%		5.50%
Aggregate principle amount	$ 300,000,000.0			$ 300,000,000.0
Capitalized debt issuance costs	$ 3,500,000	$ 4,100,000