Basis of Presentation - Depreciation (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Sep. 30, 2017
Change in accounting estimate
Property, plant and equipment, net	$ 4,883,378	$ 5,001,051
Rigs components depreciation
Change in accounting estimate
Property, plant and equipment, net	10,400
Increase in depreciation	1,000
Remainder of fiscal year	5,700
2019	1,400
2020	1,700
2021	1,600
2022	900
2023	300
Thereafter	$ 800

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

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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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- 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 expected to be recognized during the second fiscal year following the latest fiscal year.

+ References

No definition available.

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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.

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- Definition

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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-Subparagraph (SX 210.5-02(14))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(8))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6391035&loc=d3e2868-110229

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