Aggregate Provisionary Loss

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- Definition

Commitment And Contingencies [Line Items]

+ References

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- Definition

Maximum Aggregate Loss, If Securities' Price Falls To Zero And No Debts Collected

+ References

No definition available.

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- Definition

Sales price per unit of oil and gas produced.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1204
-Paragraph (b)
-Subparagraph (1)

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- Definition

Amount of decrease in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12201-110248

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- Definition

Amount awarded to other party in judgment or settlement of litigation.

+ References

No definition available.

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- Definition

Amount of unrealized and realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI).

+ References

No definition available.

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Commitments, Contingencies and Guarantees (Narrative) (Details)			9 Months Ended
	Aug. 10, 2020 USD ($)	Apr. 20, 2020 USD ($) $ / bbl	Sep. 30, 2020 USD ($)
Commitment And Contingencies [Line Items]
Aggregate loss on securities			$ 42,000,000
Maximum aggregate loss, if securities' price falls to zero and no debts collected			50,000,000
Guarantees, Fair Value Disclosure			$ 0
Oil and Gas, Average Sale Price \| $ / bbl		(37.63)
Aggregate provisionary loss		$ 88,000,000
Recognized loss		$ 104,000,000
FINRA [Member]
Commitment And Contingencies [Line Items]
Settlement, penalties agreed to paid	$ 15,000,000
SEC [Member]
Commitment And Contingencies [Line Items]
Settlement, penalties agreed to paid	11,500,000
CFTC [Member]
Commitment And Contingencies [Line Items]
Settlement, penalties agreed to paid	11,500,000
Disgorgement [Member]
Commitment And Contingencies [Line Items]
Settlement, penalties agreed to paid	$ 700,000