Name:	invest_InvestmentContractWeight
Namespace Prefix:	invest_
Data Type:	xbrli:decimalItemType
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Period Type:	instant

The average forward price on the group of price risk forward or futures contracts, such as gas futures contracts.

No definition available.

Name:	us-gaap_DerivativeAverageForwardPrice
Namespace Prefix:	us-gaap_
Data Type:	srt-types:perUnitItemType
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Period Type:	instant

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.

No definition available.

Name:	us-gaap_GuaranteeObligationsLineItems
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Data Type:	xbrli:stringItemType
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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918673-209980

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Data Type:	xbrli:durationItemType
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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

No definition available.

Name:	us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

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Name:	srt_CurrencyAxis=currency_XAU
Namespace Prefix:
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Balance Type:
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Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
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