Long-Term Debt - Scheduled Maturities of Long-Term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Sep. 30, 2017
Debt Disclosure [Abstract]
2019	$ 58,650
2020	14,600
2021	164,600
2022	1,450,075
Total long-term debt	1,687,925
Current portion of long-term debt	14,600	$ 14,600
Less: Original issue discount	1,973
Less: Financing costs	28,210
Long-term debt, net	$ 1,643,142	$ 1,574,882

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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 debt discount to be amortized after one year or the normal operating cycle, if longer.

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Amount, after accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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