CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 13,202	$ 69,690
Other comprehensive income (loss):
Unrecoverable pension benefit plan costs, net of taxes of $0 and $0, respectively	0	(13,663)
Amortization of defined benefit pension plans, net of taxes of $60 and $0, respectively	154	297
Other comprehensive income (loss), net of tax	154	(13,366)
Comprehensive income	13,356	56,324
Comprehensive loss attributable to noncontrolling interest	(129)	(227)
Comprehensive income attributable to California Water Service Group	$ 13,485	$ 56,551