Debt - Maturities of Long-Term Debt (Details) $ in Thousands	Dec. 31, 2018 USD ($)
Debt Disclosure [Abstract]
2019	$ 1,226
2020	190,392
2021	0
2022	19,300
2023	700,000
Thereafter	0
Subtotal	910,918
Less unamortized debt issuance costs	(4,574)
Total outstanding debt	$ 906,344

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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, after accumulated amortization, of debt discount (premium).

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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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