Earnings Per Share and Capital Stock 2 (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Capital stock
Undistributed Earnings (Loss) Allocated to Participating Securities, Basic		$ (129,000)	$ (176,000)
Additional disclosure
Common Shares issued under DRP and the Employee Plans	88,772	44,906	56,498
Dividend Reinvestment Plan Common Stock Capital Shares Reserved for Future Issuance	1,055,948
Common Shares authorized for issuance but unissued under 401(k) Plan	387,300
Common Shares issued as a result of the exercise of stock options	30,998	32,142	52,936
Cash proceeds from the exercise of stock options	$ 519,000	$ 546,000	$ 909,000
Proceeds from Stock Options Exercised, Distributed to Subsidiaries	0	0	0
AWR
Additional disclosure
Cash proceeds from the exercise of stock options	$ 519,000	546,000	$ 909,000
GSWC
Additional disclosure
Stock Issued During Period, Value, New Issues		$ 47,500,000
Common Stock [Member]
Additional disclosure
Common Shares issued under DRP and the Employee Plans	89,000	77,000	110,000
Common Stock [Member] | GSWC
Additional disclosure
Common Shares issued under DRP and the Employee Plans		19