Percentage of principle balance used to calculate amount of quarterly installments due.

No definition available.

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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Balance Type:	na
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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.

+ Details

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Period Type:	duration

- 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))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Period Type:	duration

- 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.

+ Details

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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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-SubTopic 30
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-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Balance Type:	debit
Period Type:	instant

- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- 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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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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Long-Term Debt - Additional Information (Details) - USD ($) $ in Millions					12 Months Ended
	Feb. 21, 2019	Aug. 15, 2018	Apr. 28, 2017	Dec. 18, 2013	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Sep. 20, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Debt repayments					$ 10.4	$ 10.4	$ 13.0
Debt voluntary repayment					24.6	80.0	120.0
Debt borrowings during the period					34.5	80.0	$ 120.0
Long-term debt, fair value					$ 1,148.7	$ 1,143.5
Receivables Financing Agreement \| Wholly-owned Subsidiary
Debt Instrument [Line Items]
Credit agreement, maximum borrowing capacity	$ 200.0		$ 175.0					$ 235.0	$ 250.0
Debt instrument, maturity date	Feb. 20, 2022		Apr. 27, 2020
Weighted average interest rate					1.60%	2.70%
Commitment fee for unused balance of facility					0.40%
Debt voluntary repayment					$ 34.5	$ 80.0
Debt borrowings during the period					$ 24.6	80.0
LIBOR \| Maximum \| Receivables Financing Agreement \| Wholly-owned Subsidiary
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					170.00%
LIBOR \| Minimum \| Receivables Financing Agreement \| Wholly-owned Subsidiary
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					140.00%
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				$ 1,460.0
Credit Agreement \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term				5 years
Credit agreement, maximum borrowing capacity				$ 210.0
Amended Credit Agreement
Debt Instrument [Line Items]
Percentage of principle balance used to calculate debt repayments amount of quarterly installments due					0.25%
Amended Credit Agreement \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term		5 years
Credit agreement, maximum borrowing capacity		$ 260.0
Amended Credit Agreement \| Series B Term Loan
Debt Instrument [Line Items]
Debt instrument, term		7 years
Credit agreement, maximum borrowing capacity		$ 1,037.0
Debt instrument, original discount		$ 2.8
Debt instrument, basis spread on variable rate		2.50%
Debt repayments					$ 10.4	$ 10.4
Debt instrument, maturity date		Aug. 15, 2025
Debt instrument, effective interest rate		2.50%
Weighted average interest rate					2.70%	3.50%
Previous Revolving Credit Facility \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Credit agreement, maximum borrowing capacity				$ 210.0
Line of credit facility, amount outstanding balance					$ 0.0	$ 0.0
Letters of credits, outstanding amount					$ 52.3	78.0
Previous Revolving Credit Facility \| First Lien Revolving Credit Facility \| Scenario One Depending on Leverage Ratio
Debt Instrument [Line Items]
Commitment fee for unused balance of facility					0.05%
Previous Revolving Credit Facility \| First Lien Revolving Credit Facility \| Scenario Two Depending on Leverage Ratio
Debt Instrument [Line Items]
Commitment fee for unused balance of facility					0.375%
Revolving Credit Facility \| First Lien Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term		5 years
Credit agreement, maximum borrowing capacity		$ 260.0
Debt repayments					$ 0.0	$ 70.0
Debt instrument, maturity date		Aug. 15, 2023
Line of credit facility, interest rate during period						2.30%	2.50%
Revolving Credit Facility \| First Lien Revolving Credit Facility \| LIBOR \| Maximum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.50%
Revolving Credit Facility \| First Lien Revolving Credit Facility \| LIBOR \| Minimum
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate		2.00%