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REVENUE FROM CONTRACTS WITH CUSTOMERS - NARRATIVE (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Sep. 30, 2020
Disaggregation of Revenue [Line Items] |  |  |
Contract with customer, liability, current | $ 391 |  | $ 1,097
Contract with customer, liability, revenue recognized | 789 | $ 707 |
Revenue, remaining performance obligation (backlog) | $ 2,609 |  |
Percentage anticipated to be recognized in next 12 months | 7.00% |  |
Capitalized contract cost net, preconstruction | $ 105 |  | $ 145
Minimum |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract receivable retainage percentage | 5.00% |  |
Maximum |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Contract receivable retainage percentage | 10.00% |  |

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- Definition Amount, after accumulated amortization and accumulated impairment loss, of asset recognized from cost incurred to obtain or fulfill contract with customer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 340 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=68051541&loc=SL49131252-203054 + Details
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130531-203044 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130532-203044 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130549-203045 + Details
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- Definition Amount of transaction price allocated to performance obligation that has not been recognized as revenue. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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- Definition Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 + Details
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