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Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | $ 1,395 |  |
Balance at Beginning of Period | 29,614 |  |
Charged to Costs and Expenses, net of Recoveries | 1,009 | $ (380) | $ 763
Balance at End of Period | 1,453 | 1,395 |
Balance at End of Period | 30,551 | 29,614 |
Inventory Obsolescence Reserve |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 29,614 | 9,674 | 6,675
Charged to Costs and Expenses | 4,353 | 21,472 | 11,212
(Deductions) and Additions | (3,416) | (1,532) | (8,213)
Balance at End of Period | 30,551 | 29,614 | 9,674
Allowance for Doubtful Accounts on Accounts and Financing Receivables |  |  |
Valuation And Qualifying Accounts Disclosure [Line Items] |  |  |
Balance at Beginning of Period | 2,415 | 2,949 | 2,516
Charged to Costs and Expenses, net of Recoveries | 1,009 | (380) | 763
(Deductions) and Additions | (122) | (154) | (330)
Balance at End of Period | $ 3,302 | $ 2,415 | $ 2,949

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- Definition Provision for recovery of doubtful accounts. + 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 A valuation allowance for trade and other receivables due to an Entity within one year (or the normal operating cycle, whichever is longer) that are expected to be uncollectible. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5074-111524 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 210.5-02.4) -URI http://asc.fasb.org/extlink&oid=6877327&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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 35 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=68049868&loc=SL66093879-108312 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2) -URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 35 -Paragraph 1C -URI http://asc.fasb.org/extlink&oid=68049868&loc=SL66093883-108312 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66092785&loc=d3e4542-108314 + Details
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- Definition Amount of increase (decrease) in valuation and qualifying accounts and reserves. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SX 210.12-09) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690 + Details
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