Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
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Summary of Significant Accounting Policies - Schedule of Inter-Company Transactions (Details) - Affiliated Entity - Spire Missouri - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Spire Marketing Inc \| Regulated Operation
Related Party Transaction [Line Items]
Purchases of natural gas from Spire Marketing Inc.	$ 10.9	$ 12.3	$ 43.7	$ 81.3
Sales of natural gas to Spire Marketing Inc.		0.2		1.6
Spire STL Pipeline LLC \| Unregulated Operation
Related Party Transaction [Line Items]
Transportation services received from	8.0		19.8
Spire NGL Inc. \| Unregulated Operation
Related Party Transaction [Line Items]
Transportation services received from	$ 0.3	$ 0.3	$ 0.8	$ 0.8