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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Acquisitions - Narrative (Details) $ in Thousands			3 Months Ended
Acquisitions - Narrative (Details) $ in Thousands	Nov. 06, 2025	Jun. 01, 2023 USD ($) a	Dec. 31, 2026 USD ($)
Subsequent Event \| Vectren Energy Delivery of Ohio, LLC \| Term Loan Facility, Commitment Letter
Acquisition [Line Items]
Debt instrument, term	364 days
Subsequent Event \| Forecast \| Vectren Energy Delivery of Ohio, LLC
Acquisition [Line Items]
Total consideration			$ 2,620,000
Payments to acquire businesses, gross			1,420,000
Subsequent Event \| Forecast \| Vectren Energy Delivery of Ohio, LLC \| Promissory Note
Acquisition [Line Items]
Debt instrument, face amount			$ 1,200,000
Debt instrument, term			364 days
Interest rate (in percent)			6.50%
SWN Upstream Asset Acquisition
Acquisition [Line Items]
Total consideration		$ 124,758
Net acres acquired in Appalachia \| a		34,000