Acquisitions - Schedule of Unaudited Pro Forma Financial Information Adjustments (Details) - Piedmont Tennessee Transaction [Member] - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
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Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2026 |
Mar. 31, 2025 |
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| Business Combination, Pro Forma Information [Line Items] | ||||
| Total Operating Revenues | $ 1,167.8 | $ 1,110.5 | $ 1,980.7 | $ 1,821.1 |
| Net Income | $ 263.3 | $ 224.3 | $ 373.2 | $ 312.7 |
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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. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount, after tax, of pro forma income (loss) of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of pro forma revenue of combined entity as if acquisition date of business combination occurred as of beginning of period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Details
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