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REVENUE - Contract Balances (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Jun. 30, 2020 | Sep. 30, 2019
Revenue from Contract with Customer [Abstract] |  |
Contract costs and recognized income not yet billed, net of progress payments | $ 92,143,000 | $ 105,111,000
Decrease in contract assets balance | 12,968,000 |
Contract costs and recognized income not yet billed, noncurrent | 7,058,000 | 13,100,000
Reserves for contract risk | 1,874,000 | 0
Contract liabilities | 20,719,000 | $ 26,259,000
Increase (decrease) in contract liabilities | $ (5,540,000) |

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- Definition Contract With Customer, Asset, And Capitalized Contract Cost, Net, Current + References No definition available. + Details
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- Definition Contract With Customer, Asset, And Capitalized Contract Cost, Net, Noncurrent + References No definition available. + Details
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- Definition Increase (Decrease) Contract With Customer, Asset, And Capitalized Contract Cost, Net, Current + References No definition available. + Details
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- Definition Amount of allowance for credit loss for right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121556615&loc=SL49130533-203044 Reference 2: 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=121599878&loc=SL82895884-210446 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 13 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121599337&loc=SL82919249-210447 + Details
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X
- 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 increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 + Details
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- References No definition available. + Details
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