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Leases - Additional Information (Details) | 12 Months Ended
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Sep. 30, 2020
Lessee Lease Description [Line Items] |
Operating lease, existence of option to extend | true
Operating lease, option to extend | The lease agreement covering the Company’s primary office space in St. Louis extends through February 2035, with an option to renew for an additional five years
Operating lease extend period | 2028-12
Operating lease, renewal term | 5 years
Operating lease, existence of option to terminate | true
Operating lease, existence of option to terminate period | with options to terminate three years
Spire Missouri |
Lessee Lease Description [Line Items] |
Operating lease, existence of option to extend | true
Operating lease, option to extend | The lease agreement covering Spire Marketing and Spire Storage office space in Houston extends through December 2028, with options to terminate three years earlier or to renew for an additional five years
Operating lease extend period | 2035-02
Operating lease, renewal term | 5 years
Spire Alabama |
Lessee Lease Description [Line Items] |
Operating lease, existence of option to extend | true
Operating lease, option to extend | Spire Alabama’s lease agreement for office space in Birmingham extends through January 2024.
Operating lease extend period | 2024-01

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- Definition Lessee operating lease extend period. + References No definition available. + Details
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- Definition 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. + References No definition available. + Details
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- Definition Indicates (true false) whether lessee has option to extend operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Indicates (true false) whether lessee has option to terminate operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Description of terms and conditions of option to terminate lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980 + Details
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- Definition Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References 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=121609121&loc=SL77918673-209980 + Details
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- Details
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- Details
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