Debt Long-Term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 3,340	$ 3,689
Long-term Debt	839,196	676,863
Long-term debt, current portion	11,923	12,444
Long-term debt, net of current portion	636,273	648,419
Unsecured notes
Debt Instrument [Line Items]
Long-term Debt, Gross	425,000
Credit Agreement
Debt Instrument [Line Items]
Long-term Debt, Gross	226,536	239,552
Revolving Credit Facility
Debt Instrument [Line Items]
Long-term Debt, Gross	191,000	16,000
Unsecured notes
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 425,000	$ 425,000

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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

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

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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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