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Summary of Significant Accounting Policies - Additional Information (Details 2) - USD ($) $ in Millions | 12 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2018
Summary Of Significant Accounting Policies [Line Items] |  |  |
Percentage of importance to income approach used for evaluation of recoverability of goodwill (as a percent) | 75.00% |  |
Net foreign currency transaction gains (losses) related to continuing operations | $ (2.7) | $ 2.1 | $ (3.8)
Minimum | Buildings and Improvements |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 10 years |  |
Minimum | Machinery and Equipment |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 4 years |  |
Minimum | Software and Related Costs |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 3 years |  |
Maximum | Buildings and Improvements |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 40 years |  |
Maximum | Machinery and Equipment |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 25 years |  |
Maximum | Software and Related Costs |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Useful life | 10 years |  |

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- Definition Amount before tax of foreign currency transaction realized gain (loss) recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109240200&loc=d3e30690-110894 + Details
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- Definition Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment. + References No definition available. + Details
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