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Leases - Narrative (Details) $ in Millions | 12 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2021 USD ($) renewal_option | Sep. 30, 2020 USD ($) | Oct. 01, 2019 USD ($)
Lessee, Lease, Description [Line Items] |  |  |
Number of options to renew (or more) | renewal_option | 1 |  |
Termination period | 2 years |  |
Operating right of use assets | $ 125.3 | $ 101.5 | $ 33.1
Operating lease liabilities | $ 146.6 | $ 118.7 | $ 36.2
Building | Minimum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Renewal term | 3 years |  |
Building | Maximum |  |  |
Lessee, Lease, Description [Line Items] |  |  |
Renewal term | 10 years |  |

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- Definition Lessee, Operating Lease, Minimum Number Of Options To Renew + References No definition available. + Details
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- Definition Lessee, Operating Lease, Termination Period + References No definition available. + Details
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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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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980 + Details
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- Definition Present value of lessee's discounted obligation for lease payments from operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Definition Amount of lessee's right to use underlying asset under operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123391704&loc=SL77918627-209977 + Details
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- Details
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