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Inventories - Additional Information (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2016
Inventory Disclosure [Abstract] |  |  |
Inventory obsolescence expense | $ 4,353 | $ 21,472 | $ 11,212
Raw materials include semi-finished goods and component parts | $ 29,000 | $ 43,200 |

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- Definition Inventory obsolescence expense. + References No definition available. + Details
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- Definition Carrying amount, net of reserves and adjustments, as of the balance sheet date of merchandise or goods which are partially completed. This inventory is generally comprised of raw materials, labor and factory overhead costs, which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing. + 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)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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