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Leases - Operating Lease Cost Cash Flow and Noncash Information (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2020 USD ($)
Lessee Lease Description [Line Items] |
Operating lease cost, including amounts capitalized | $ 8.7
Cash flow and noncash information about operating leases: |
Operating cash flows representing cash paid for amounts included in the measurement of lease liabilities | 8.5
Right-of-use assets obtained in exchange for lease liabilities | 71.1
Spire Missouri Inc |
Lessee Lease Description [Line Items] |
Operating lease cost, including amounts capitalized | 0.5
Cash flow and noncash information about operating leases: |
Operating cash flows representing cash paid for amounts included in the measurement of lease liabilities | 0.5
Right-of-use assets obtained in exchange for lease liabilities | 2.1
Spire Alabama |
Lessee Lease Description [Line Items] |
Operating lease cost, including amounts capitalized | 3.5
Cash flow and noncash information about operating leases: |
Operating cash flows representing cash paid for amounts included in the measurement of lease liabilities | 3.3
Right-of-use assets obtained in exchange for lease liabilities | $ 10.0

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- Definition Cash flow and noncash information about operating leases. + 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 Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121603541&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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- Definition Amount of increase in right-of-use asset obtained in exchange for operating lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(2) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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