SCHEDULE I - CONDENSED FINANCIAL INFORMATION OF PARENT - Condensed Statements of Cash Flows (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Condensed financial statements
Net cash provided (used)	$ 198,732	$ 67,683	$ 117,799
Cash Flows From Investing Activities:
Net cash provided (used)	(232,780)	(188,764)	(167,102)
Cash Flows From Financing Activities:
Proceeds from issuance of Common Shares to AWR (parent)	88,814	0	0
Dividends paid	(67,017)	(61,195)	(56,356)
Net cash provided (used)	46,636	129,157	50,337
Net change in cash and cash equivalents	12,588	8,076	1,034
Cash and cash equivalents, beginning of period	14,073
Cash and cash equivalents, end of year	26,661	14,073
Parent Company
Condensed financial statements
Net cash provided (used)	47,069	67,041	56,398
Cash Flows From Investing Activities:
Loans (made to)/repaid from, wholly-owned subsidiaries	17,000	121,000	(81,000)
Increase in investment of subsidiary	(62,000)	(10,000)	0
Net cash provided (used)	(45,000)	111,000	(81,000)
Cash Flows From Financing Activities:
Proceeds from issuance of Common Shares to AWR (parent)	88,814	0	0
Net changes in notes payable to banks	(21,500)	(113,392)	81,000
Dividends paid	(67,017)	(61,195)	(56,356)
Net cash provided (used)	297	(174,587)	24,644
Net change in cash and cash equivalents	2,366	3,454	42
Cash and cash equivalents, beginning of period	3,547	93	51
Cash and cash equivalents, end of year	$ 5,913	$ 3,547	$ 93