PROPERTY, PLANT AND EQUIPMENT - Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment
Depreciation	$ 141,460	$ 143,267
Abandonments	1,000	$ 7,300
Remainder of fiscal year	700
2020	(600)
2021	(600)
2022	(400)
2023	(100)
2024	(100)
Thereafter	(100)
Rigs components depreciation
Property, Plant and Equipment
Increase in depreciation	$ 2,500

The amount of increase (decrease) in depreciation during the period.

No definition available.

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- Definition

Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected to be recognized after the sixth fiscal year following the latest fiscal year.

+ References

No definition available.

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Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected to be recognized in the remainder of the fiscal year.

+ References

No definition available.

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Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected to be recognized during the fifth fiscal year following the latest fiscal year.

+ References

No definition available.

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Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected to be recognized during the sixth fiscal year following the latest fiscal year.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected to be recognized during the third fiscal year following the latest fiscal year.

+ References

No definition available.

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Amount of increase (decrease) in depreciation expense due the change in estimated useful life for property plant and equipment with a finite life expected expected to be recognized during the second fiscal year following the latest fiscal year.

+ References

No definition available.

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- Definition

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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- Definition

Loss recognized as a result of the initial and subsequent write-down of a long-lived asset's carrying amount to fair value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109226691&loc=d3e2921-110230

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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