Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 182,701	$ 154,900
Regulatory balancing account revenue	21,272	115,849
Total operating revenue	203,973	270,749
Total non-regulated revenue	5,081	5,098
Residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	105,433	92,492
Business
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	40,548	34,549
Multiple residential
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	19,203	16,869
Industrial
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	6,405	6,640
Public authorities
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	9,245	6,962
Other
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,867	(2,612)
Operating and maintenance revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	3,267	3,248
Other non-regulated revenue
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,248	1,229
Non-regulated revenue from contracts with customers
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,515	4,477
Lease revenue	566	621
Total non-regulated revenue	$ 5,081	$ 5,098

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.

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