Long-term Debt - Debt Table (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Debt issuance costs	$ (6,440)	$ (7,730)
Long-term debt, net	293,560	303,080
Senior Notes [Member]
Debt Instrument [Line Items]
Debt	300,000	300,000
Credit Agreement [Member]
Debt Instrument [Line Items]
Debt	$ 0	$ 10,810

Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 210
-Section S99
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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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-Name Accounting Standards Codification
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-SubTopic 10
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Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.

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