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v3.25.3

Revenue and Accounts Receivable - Disaggregation of Revenue (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Disaggregation of Revenue [Line Items] |  |  |
Total operating revenues | $ 4,702,755 | $ 4,165,187 | $ 4,275,357
Mississippi recovery of uncollectible accounts |  | (4,192) |
Distribution |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Total operating revenues | 4,422,355 | 3,912,134 | 4,096,661
Pipeline and Storage |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Total operating revenues | 280,400 | 253,053 | 178,696
Operating Segments |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Total operating revenues | 5,490,697 | 4,853,170 | 4,884,864
Operating Segments | Distribution |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 4,361,803 | 3,847,167 | 4,051,778
Alternative revenue program revenues | 49,215 | 52,401 | 43,139
Other revenues | 14,379 | 15,573 | 4,773
Total operating revenues | 4,425,397 | 3,915,141 | 4,099,690
Operating Segments | Distribution | Gas sales revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 4,196,804 | 3,700,731 | 3,920,314
Operating Segments | Distribution | Gas sales revenues | Residential |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 2,877,456 | 2,542,438 | 2,606,658
Operating Segments | Distribution | Gas sales revenues | Commercial |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 1,145,710 | 1,006,593 | 1,100,773
Operating Segments | Distribution | Gas sales revenues | Industrial |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 122,284 | 100,363 | 151,538
Operating Segments | Distribution | Gas sales revenues | Public authority and other |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 51,354 | 51,337 | 61,345
Operating Segments | Distribution | Transportation revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 151,876 | 134,600 | 121,420
Operating Segments | Distribution | Miscellaneous revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 13,123 | 11,836 | 10,044
Operating Segments | Pipeline and Storage |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 1,131,764 | 998,687 | 824,148
Alternative revenue program revenues | (66,464) | (60,658) | (38,974)
Other revenues | 0 | 0 | 0
Total operating revenues | 1,065,300 | 938,029 | 785,174
Operating Segments | Pipeline and Storage | Gas sales revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 0 | 0 | 0
Operating Segments | Pipeline and Storage | Gas sales revenues | Residential |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 0 | 0 | 0
Operating Segments | Pipeline and Storage | Gas sales revenues | Commercial |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 0 | 0 | 0
Operating Segments | Pipeline and Storage | Gas sales revenues | Industrial |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 0 | 0 | 0
Operating Segments | Pipeline and Storage | Gas sales revenues | Public authority and other |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 0 | 0 | 0
Operating Segments | Pipeline and Storage | Transportation revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | 1,119,015 | 982,795 | 811,968
Operating Segments | Pipeline and Storage | Miscellaneous revenues |  |  |
Disaggregation of Revenue [Line Items] |  |  |
Revenues from contracts with customers | $ 12,749 | $ 15,892 | $ 12,180

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