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v3.25.3

Revenue from Contracts with Customers - Narrative (Details) $ in Millions | 12 Months Ended
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Sep. 30, 2025 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Payment period for Integrated Upstream and Gathering segment invoices | 30 days
Period after invoice received in which payment is typically due for Integrated Upstream and Gathering segments | 10 days
Settlement period for receivables or customer advances related to Utility segment budget billing | 1 year
Annual reconciliation period for Utility segment alternative revenue programs | 24 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 228.0
Remaining performance obligations, period | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 214.1
Remaining performance obligations, period | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 162.7
Remaining performance obligations, period | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 129.7
Remaining performance obligations, period | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 122.7
Remaining performance obligations, period | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2030-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Remaining performance obligations | $ 529.1
Remaining performance obligations, period |

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- Definition Period in which remaining performance obligation is expected to be recognized as revenue, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (b)(1) -SubTopic 10 -Topic 606 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479806/606-10-50-13 + Details
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