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Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | $ 496 |
Balance at Beginning of Period | 34,960 |
Charged to Costs and Expenses, net of Recoveries | (76) | $ 63
Balance at End of Period | 428 | 496
Balance at End of Period | 36,936 | 34,960
Inventory Obsolescence Reserve |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | 34,960 | 32,050
Charged to Costs and Expenses | 3,001 | 4,726
(Deductions) and Additions | (1,025) | (1,816)
Balance at End of Period | 36,936 | 34,960
Allowance for Doubtful Accounts on Accounts and Financing Receivables |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |
Balance at Beginning of Period | 496 | 951
Charged to Costs and Expenses, net of Recoveries | (76) | 63
(Deductions) and Additions | 8 | (518)
Balance at End of Period | $ 428 | $ 496

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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=123577603&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=124255206&loc=SL82895884-210446 + Details
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