Risk Management (Narrative) (Details) - Price Risk Contracts Member - Maximum	9 Months Ended
Sep. 30, 2021
Derivative [Line Items]
Remaining maturity	36 months
Percent of contracts expiring in the next twelve months	86.00%

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.

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