Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Sep. 30, 2018
Debt Instrument [Line Items]
Financing costs, net	$ (19,190)	$ (20,046)
Total debt, net	1,150,006	1,154,242
Less: Current portion of long-term debt	10,370	12,963
Long-term debt, net	1,139,636	1,141,279
Series B Term Loan
Debt Instrument [Line Items]
Debt instruments net of original issue discount	1,029,196	1,034,288
Receivables Financing Agreement
Debt Instrument [Line Items]
Debt instruments net of original issue discount	$ 140,000	$ 140,000

Debt instrument carrying amount net of issue discount.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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