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Summary of Significant Accounting Policies (Schedule of Reserves for Excess and Obsolete Inventory) (Details) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2019
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at beginning of year | $ 11.7 | $ 7.5 | $ 5.1
Provision charged to expense | (5.9) | (4.7) | (3.4)
Inventory Valuation Allowances and Reserves, Deduction | (3.6) | (0.7) | (1.2)
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment | 0.8 | 0.2 | 0.2
Balance at end of year | $ 14.8 | $ 11.7 | $ 7.5

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- Definition Amount of valuation reserve for inventory. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 5.BB) -URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100047-122729 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.6(a)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount of loss from reductions in inventory due to subsequent measurement adjustments, including, but not limited to, physical deterioration, obsolescence, or changes in price levels. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=116847112&loc=d3e4542-108314 + Details
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