Percentage points added to the reference rate to compute the variable rate on the debt instrument.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility first became available, in CCYY-MM-DD format.

+ References

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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-SubTopic 10
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-Paragraph 15
-Subparagraph (b)
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- Definition

Amount of cash outflow for payment of an obligation from a lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Long-Term Debt - Additional Information (Details) - USD ($)					6 Months Ended
	Feb. 21, 2019	Aug. 15, 2018	Apr. 28, 2017	Dec. 18, 2013	Mar. 31, 2020	Mar. 31, 2019	Sep. 30, 2019
Debt Instrument [Line Items]
Debt repayments					$ 5,200,000	$ 7,800,000
Debt borrowings during the period					70,000,000	10,000,000
Debt voluntary repayment					10,000,000	10,000,000
Level 2 Inputs
Debt Instrument [Line Items]
Long-term debt, fair value					1,132,800,000		$ 1,166,600,000
Receivables Financing Agreement \| Wholly-owned Subsidiary
Debt Instrument [Line Items]
Credit agreement, maximum borrowing capacity	$ 200,000,000		$ 175,000,000
Debt instrument, maturity date	Feb. 20, 2022		Apr. 27, 2020
Debt borrowings during the period					80,000,000	85,000,000
Debt voluntary repayment					50,000,000	$ 75,000,000
Credit Agreement \| First Lien Credit Facility Term Loans
Debt Instrument [Line Items]
Credit agreement date				Dec. 18, 2013
Debt instrument, term				7 years
Credit agreement, maximum borrowing capacity				$ 1,460,000,000
Credit Agreement \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term				5 years
Credit agreement, maximum borrowing capacity				$ 210,000,000
Amended Credit Agreement \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term		5 years
Credit agreement, maximum borrowing capacity		$ 260,000,000
Amended Credit Agreement \| Series B Term Loan
Debt Instrument [Line Items]
Debt instrument, term		7 years
Credit agreement, maximum borrowing capacity		$ 1,037,000,000
Debt instrument, original discount		$ 2,800,000
Debt instrument, basis spread on variable rate		2.50%
Debt repayments					5,200,000
Revolving Credit Facility \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement, maximum borrowing capacity					210,000,000
Line of credit facility, amount outstanding balance					60,000,000		$ 0
Revolving Credit Facility \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement, maximum borrowing capacity		$ 260,000,000
Debt repayments					10,000,000
Debt instrument, maturity date		Aug. 15, 2023
Debt borrowings during the period					$ 70,000,000
Revolving Credit Facility \| First Lien Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.00%
Revolving Credit Facility \| First Lien Revolving Credit Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.50%