Represents the number of geographical areas operated to minimize the potential impact of risks.

No definition available.

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- Definition

The number of rigs which were expropriated by the Government.

+ References

No definition available.

+ Details

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13537-108611

+ Details

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6450222&loc=d3e30840-110895

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30700-110894

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64836518&loc=d3e30690-110894

+ Details

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Balance Type:	credit
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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.

+ Details

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- Details

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- Details

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Data Type:	na
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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_SalesRevenueNetMember
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- Details

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- Details

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- Details

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Data Type:	na
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- Details

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- Details

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International Risk Factors (Details) $ in Millions	3 Months Ended			6 Months Ended
International Risk Factors (Details) $ in Millions	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2015 USD ($)	Mar. 31, 2018 USD ($) item	Mar. 31, 2017 USD ($)	Jun. 30, 2010 item
International Risk Factors
Foreign currency gains (losses) \| $	$ 0.2	$ (0.6)		$ (1.4)	$ (2.0)
Venezuela
International Risk Factors
Number of rigs expropriated by Venezuelan government \| item						11
Argentina
International Risk Factors
Foreign currency gains (losses) \| $			$ (8.5)
Operating revenues \| Geographic concentration risk \| South America
International Risk Factors
Concentration percentage				95.80%
Minimum
International Risk Factors
Number of geographical areas of operation to minimize risks \| item				1
Contract Drilling: \| Operating revenues \| Geographic concentration risk \| International locations
International Risk Factors
Concentration percentage				10.10%