Revenue - Schedule of Disaggregation of revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Disaggregation of Revenue [Line Items]
Total Operating Revenues	$ 5,124,915	$ 4,695,991	$ 4,324,385
Retail Electric Service | Residential
Disaggregation of Revenue [Line Items]
Total Operating Revenues	2,562,822	2,289,196	2,046,111
Retail Electric Service | Non-Residential
Disaggregation of Revenue [Line Items]
Total Operating Revenues	2,334,925	2,048,416	1,767,616
Wholesale Energy Sales
Disaggregation of Revenue [Line Items]
Total Operating Revenues	96,857	208,985	383,126
Transmission Services for Others
Disaggregation of Revenue [Line Items]
Total Operating Revenues	119,038	138,631	116,628
Other Sources
Disaggregation of Revenue [Line Items]
Total Operating Revenues	$ 11,273	$ 10,763	$ 10,904