Financial Statement Schedule - Schedule of Principal Payments on Long-Term Debt (Details) $ in Thousands	Dec. 31, 2024 USD ($)
Condensed Financial Statements, Captions [Line Items]
2025	$ 3,664
2026	23,757
2027	3,011
2028	44,502
2029	325,425
Thereafter	1,319,465
SJW Group
Condensed Financial Statements, Captions [Line Items]
2025	0
2026	0
2027	0
2028	0
2029	310,000
Thereafter	$ 250,000

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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