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Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2020 | Sep. 30, 2019
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | $ 951 |
Balance at Beginning of Period | 32,050 |
Charged to Costs and Expenses, net of Recoveries | 63 | $ 436
Balance at End of Period | 496 | 951
Balance at End of Period | 34,960 | 32,050
Inventory Obsolescence Reserve |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | 32,050 | 30,551
Charged to Costs and Expenses | 4,529 | 4,614
(Deductions) and Additions | (1,816) | (3,115)
Balance at End of Period | 34,763 | 32,050
Allowance for Doubtful Accounts on Accounts and Financing Receivables |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | 951 | 3,302
Charged to Costs and Expenses, net of Recoveries | 63 | 436
(Deductions) and Additions | (518) | (2,787)
Balance at End of Period | $ 496 | $ 951

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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. + 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(4) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121599878&loc=SL82895884-210446 + Details
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