Debt - Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Disclosure [Abstract]
Remaining 2018	$ 120,179
2019	20,714
2020	20,714
2021	20,714
2022	120,714
Thereafter	2,409,653
Total debt	2,712,688	$ 2,517,216
Unamortized discounts and deferred financing costs	(40,985)
Total debt per balance sheet	$ 2,671,703	$ 2,475,887

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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 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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