Revenue - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Disaggregation of Revenue [Line Items]
Operating revenues	$ 1,358,751	$ 1,308,994	$ 2,391,031	$ 2,260,706
Regulatory cost recovery revenue	14,000	6,000	27,000	15,000
Electric and Transmission Service
Disaggregation of Revenue [Line Items]
Operating revenues	$ 1,345,000	$ 1,303,000	$ 2,364,000	$ 2,246,000