Acquisitions - Summary of Preliminary Purchase Price Allocation and Estimated Fair Values of Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Millions |
9 Months Ended | |||
|---|---|---|---|---|
Mar. 31, 2026 |
Jun. 30, 2026 |
Jun. 30, 2025 |
Sep. 30, 2025 |
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| Business Combination [Line Items] | ||||
| Acquisition consideration: | $ 2,500.8 | $ 0.0 | ||
| Liabilities assumed: | ||||
| Goodwill | 1,895.2 | $ 1,171.6 | $ 1,171.6 | |
| Piedmont Tennessee Transaction [Member] | ||||
| Business Combination [Line Items] | ||||
| Acquisition consideration: | $ 2,500.8 | |||
| Assets acquired: | ||||
| Utility plant | 1,829.4 | |||
| Accounts receivable (net allowance of $1.7) | 65.2 | |||
| Inventories | 7.1 | |||
| Current regulatory assets | 33.4 | |||
| Other current assets | 35.6 | |||
| Non-current regulatory assets | 42.1 | |||
| Other non-current assets | 0.4 | |||
| Total assets acquired | 2,013.2 | |||
| Liabilities assumed: | ||||
| Accounts payable | 33.5 | |||
| Other current liabilities | 35.6 | |||
| Non-current regulatory liabilities | 173.5 | |||
| Other non-current liabilities | 11.5 | |||
| Total liabilities assumed | 254.1 | |||
| Net assets acquired | 1,759.1 | |||
| Goodwill | $ 741.7 | $ 741.7 | ||
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- Definition Business combination, recognized identifiable assets acquired and liabilities assumed, regulatory assets, current. No definition available.
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- Definition Business combination, recognized identifiable assets acquired and liabilities assumed, regulatory assets, non-current. No definition available.
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- Definition Business combination, recognized identifiable assets acquired and liabilities assumed, regulatory liabilities, noncurrent. No definition available.
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- Definition Business combination, recognized identifiable assets acquired and liabilities assumed, utility plant, current. No definition available.
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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 of asset acquired in business combination and recognized at acquisition date. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of asset acquired in business combination and recognized at acquisition date, classified as other and current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of receivable acquired in business combination and recognized at acquisition date, classified as current. Includes, but is not limited to, receivable from customer for product and service. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of accounts payable assumed in business combination and recognized at acquisition date, classified as current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of liability assumed in business combination and recognized at acquisition date, classified as other and current. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of inventory acquired in business combination and recognized at acquisition date, classified as current. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of liability assumed in business combination and recognized at acquisition date. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Amount of asset acquired in excess of (less than) liability assumed in business combination and recognized at acquisition date. Excludes goodwill. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of liability assumed in business combination and recognized at acquisition date, classified as noncurrent. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of asset acquired in business combination and recognized at acquisition date, classified as other and noncurrent. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Details
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