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Derivative Instruments and Hedging Activities - Open NYMEX Natural Gas Futures Positions (Details) - Spire Missouri - Natural Gas Futures Purchased MMBTU in Millions | 12 Months Ended
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Sep. 30, 2020 MMBTU
Derivative [Line Items] |
Notional (MMBtu millions) | 25.9
Maximum Term (Months) | 12 months

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- Definition Nominal energy measure used to calculate payments on a derivative instrument. + References No definition available. + Details
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- Definition Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
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- Details
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- Details
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