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v3.25.3

Segment Information - Schedule of Income Statements and Capital Expenditures By Segment (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Segment Reporting Information [Line Items] |  |  |
Operating revenues | $ 4,702,755 | $ 4,165,187 | $ 4,275,357
Operation and maintenance expense | 874,910 | 808,435 | 743,658
Depreciation and amortization expense | 734,745 | 669,972 | 604,327
Interest charges | 171,678 | 190,632 | 137,281
Income tax expense | 279,280 | 192,881 | 113,779
Other segment items | 2,231,330 | 1,948,355 | 2,399,957
Net income | 1,198,754 | 1,042,895 | 885,862
Capital expenditures | 3,561,399 | 2,937,124 | 2,805,973
Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | 4,422,355 | 3,912,134 | 4,096,661
Operation and maintenance expense | 644,924 | 589,864 | 543,078
Depreciation and amortization expense | 543,840 | 491,982 | 434,721
Interest charges | 99,226 | 117,086 | 77,185
Income tax expense | 150,961 | 96,041 | 60,032
Other segment items | 2,239,665 | 1,948,755 | 2,404,277
Net income | 746,781 | 671,413 | 580,397
Capital expenditures | 2,662,703 | 2,249,280 | 1,927,125
Pipeline and Storage |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | 280,400 | 253,053 | 178,696
Operation and maintenance expense | 229,986 | 218,571 | 200,580
Depreciation and amortization expense | 190,905 | 177,990 | 169,606
Interest charges | 72,452 | 73,546 | 60,096
Income tax expense | 128,319 | 96,840 | 53,747
Other segment items | (8,335) | (400) | (4,320)
Net income | 451,973 | 371,482 | 305,465
Capital expenditures | 898,696 | 687,844 | 878,848
Intersegment Eliminations |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | (787,942) | (687,983) | (609,507)
Intersegment Eliminations | Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | (3,042) | (3,007) | (3,029)
Intersegment Eliminations | Pipeline and Storage |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | (784,900) | (684,976) | (606,478)
Operating Segments |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | 5,490,697 | 4,853,170 | 4,884,864
Operating Segments | Distribution |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | 4,425,397 | 3,915,141 | 4,099,690
Operating Segments | Pipeline and Storage |  |  |
Segment Reporting Information [Line Items] |  |  |
Operating revenues | $ 1,065,300 | $ 938,029 | $ 785,174

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