Disposal Group, Including Discontinued Operation, Ownership Percentage Sold In Period

No definition available.

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- Definition

Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 45
-Paragraph 3B
-URI http://asc.fasb.org/extlink&oid=65878427&loc=SL51721525-107759

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+ Details

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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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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- Definition

Balance held at close of period in number of shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-12C.Column B)
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- Definition

Nominal or face amount on the investment owned.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Underlying
-URI http://asc.fasb.org/extlink&oid=6527499

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- Definition

Amount of judgment or settlement awarded to (against) the entity in respect of litigation.

+ References

No definition available.

+ Details

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- Definition

The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=6516133

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Sale of Weald Basin Assets (Detail) £ in Thousands, shares in Millions, $ in Millions			3 Months Ended	12 Months Ended
	Aug. 11, 2016 GBP (£) shares	Jun. 10, 2016 GBP (£)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 GBP (£)	Sep. 30, 2016 GBP (£)	Sep. 09, 2016 GBP (£)
Celtique Claim
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Settlement costs	£ 500			£ 500
Subsidiary \| Celtique Claim
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Settlement costs	500
Subsidiary \| Weald ATA, IoW ATA, and Settlement Agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Cash proceeds	£ 446
Subsidiary \| UKOG \| Asset Transfer Agreement \| UK Oil and Gas Investments
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage, sold in period		50.00%
Total consideration		£ 1,800
Subsidiary \| UKOG \| Asset Transfer Agreement \| Offshore Petroleum Licence
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Ownership percentage, sold in period		22.50%
Total consideration		£ 16
Subsidiary \| UK Oil and Gas Investments \| UKOG \| Weald ATA, IoW ATA, and Settlement Agreement
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Shares issued (in shares) \| shares	50.9
Investment, face amount	£ 703				£ 930	£ 958
Gain on disposal of discontinued operations before tax \| $			$ 1.1
Subsidiary \| UK Oil and Gas Investments \| UKOG \| Weald ATA, IoW ATA, and Settlement Agreement \| Scenario, Previously Reported
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Investment, face amount	£ 713