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WARRANTY LIABILITY - Summary of changes in warrant liability included in accrued liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2021 | Sep. 30, 2020
Movement in Standard Product Warranty Accrual [Roll Forward] |  |
Balance, beginning of period | $ 6,268 | $ 2,814
Warranties issued and changes in estimated pre-existing warranties | 15,560 | 16,291
Actual warranty costs incurred | (14,010) | (12,837)
Balance, end of period | $ 7,818 | $ 6,268

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- Definition Standard And Extended Product Warranty Accrual, Increase For Warranties Issued And Increase (Decrease) For Preexisting Warranties + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c)(5) -URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249 + Details
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- Definition The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(3,4)) -URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249 + Details
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