REVENUE - Contract Balances (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2019	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Contract assets	$ 70,727	$ 70,727	$ 82,545
Contract liabilities	(51,088)	(51,088)	(43,174)
Net contract assets	19,639	19,639	39,371
Revenue recognized related to contract liabilities	15,600	37,200
Retention amounts included in accounts receivable	3,800	3,800	$ 4,200
Retained amount expected to be collected in the next twelve months	$ 3,400	$ 3,400

Contract with Customer, Asset (Liability), Net, Current

No definition available.

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 910
-SubTopic 310
-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount billed to customers under long-term contracts or programs that have been withheld because of retainage provisions in a contract to be collected in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- References

No definition available.

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