Electric utility segment - Consolidated Variable Interest Entities (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Variable Interest Entity [Line Items]
Accounts receivable and unbilled revenues, net	$ 435,844	$ 457,171
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Accounts receivable and unbilled revenues, net	$ 320,500