Book Value of Assets Sold to Unconsolidated Subsidiary

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- Definition

[Line Items] for GAIN ON SALE OF ASSETS TO UNCONSOLIDATED SUBSIDIARIES [Table]

+ References

No definition available.

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- Definition

Initial Number Of Rigs Contributed To Joint Venture

+ References

No definition available.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 1B
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109239629&loc=SL4582445-111684

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- Definition

Aggregate cash proceeds received from a combination of transactions in which noncurrent assets are sold, which may include the sale of a business, an investment in an affiliate (including an equity method investee), property, plant and equipment and intangible assets. Excludes sales of trading, available-for-sale, and held-to-maturity securities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3179-108585

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GAIN ON SALE OF ASSETS TO UNCONSOLIDATED SUBSIDIARY GAIN ON SALE OF ASSETS TO UNCONSOLIDATED SUBSIDIARY (Details) $ in Millions			12 Months Ended
	Oct. 01, 2018 USD ($) drilling_unit	Oct. 17, 2017 USD ($) drilling_unit	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
GAIN ON SALE OF ASSETS TO UNCONSOLIDATED SUBSIDIARY [Line Items]
Proceeds from sale of assets to unconsolidated subsidiary			$ 266.0	$ 357.7	$ 0.0
Book Value of Assets Sold to Unconsolidated Subsidiary	$ 200.2	$ 200.3
Gain (Loss) on Disposition of Business			$ 65.8	$ 157.4	$ 0.0
Saudi Arabia Joint Venture [Member] \| Rowan Companies plc (Parent) [Member]
GAIN ON SALE OF ASSETS TO UNCONSOLIDATED SUBSIDIARY [Line Items]
Initial Number Of Rigs Contributed To Joint Venture \| drilling_unit	2	3