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Financing - Schedule of Variable Stock Purchase Contract Settlement Rates (Details) - Spire - Common Stock $1.00 par value | Feb. 28, 2021 $ / shares shares
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Equity Units [Line Items] |
Price divided by applicable market value to determine number of shares per stock purchase contract | $ 50.00
Maximum |
Equity Units [Line Items] |
Applicable market value per share | 78.6906
Applicable market value per share, reference price | $ 64.24
Number of shares to be purchased per stock purchase contract, settlement rate | shares | 0.7783
Minimum |
Equity Units [Line Items] |
Applicable market value per share, threshold appreciation price | $ 78.6906
Applicable market value per share | $ 64.24
Number of shares to be purchased per stock purchase contract, settlement rate | shares | 0.6354

X
- Definition Applicable market value per share. + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

X
- Definition Applicable market value per share, reference price. + References No definition available. + Details
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Namespace Prefix: | sr_
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Balance Type: | na
Period Type: | instant

X
- Definition Applicable market value per share, threshold appreciation price. + References No definition available. + Details
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- Definition Number of shares to be purchased per stock purchase contract, settlement rate. + References No definition available. + Details
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- Definition Price divided by applicable market value to determine number of shares per stock purchase contract. + References No definition available. + Details
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- Details
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- Details
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- Details
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