v3.26.1
Schedule H, Line 4i – Schedule of Assets (Held At End of Year) (Details) - EBP 005 - USD ($)
12 Months Ended
Dec. 30, 2025
Dec. 30, 2024
EBP, Schedule of Asset Held for Investment [Line Items]    
Entity tax identification number 95-1243678  
Plan number 005  
Total investments $ 230,927,099  
Participant loan, current value 3,257,645  
Asset held for investment $ 234,184,744  
Minimum    
EBP, Schedule of Asset Held for Investment [Line Items]    
Participant loan, interest rate 4.25%  
Maximum    
EBP, Schedule of Asset Held for Investment [Line Items]    
Participant loan, interest rate 9.50%  
Common stocks    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments $ 25,862,100 $ 28,624,645
Common Collective Trust    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 201,007,164  
Investment, Identifier [Axis]: American States Water Company Common Stock    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 25,066,421  
Investment, Identifier [Axis]: Boston Partners Large Cap Value Equity CTF    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 7,638,361  
Investment, Identifier [Axis]: Dodge & Cox International Stock Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 4,057,835  
Investment, Identifier [Axis]: Invesco Stable Value Trust Class B1    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 11,587,070  
Investment, Identifier [Axis]: JP Morgan US Government Market Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 318,164  
Investment, Identifier [Axis]: LSV U.S. Small Cap Value Equity Tier 7    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 735,654  
Investment, Identifier [Axis]: PIMCO Money Market Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 795,679  
Investment, Identifier [Axis]: Principal Diversified Real Asset Tier 3    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 865,326  
Investment, Identifier [Axis]: Prudential Core Plus Bond Fund Trust Class 5    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 4,742,757  
Investment, Identifier [Axis]: State Street Global All Cap Equity Ex U.S. Index Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 5,010,090  
Investment, Identifier [Axis]: State Street Russell Small/Mid Cap Index Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 13,918,043  
Investment, Identifier [Axis]: State Street S&P 500 Index Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 30,138,218  
Investment, Identifier [Axis]: State Street U.S. Bond Index NL Series Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 3,532,005  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2005 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 133,121  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2010 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 24,653  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2015 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 686,163  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2020 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 3,347,932  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2025 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 13,740,537  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2030 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 14,379,244  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2035 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 15,490,167  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2040 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 12,075,304  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2045 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 10,712,930  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2050 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 12,663,643  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2055 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 7,181,973  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2060 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 3,813,426  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2065 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 1,599,999  
Investment, Identifier [Axis]: T. Rowe Price | Retirement 2070 Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 97,035  
Investment, Identifier [Axis]: William Blair Small Mid Cap Growth Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments 3,412,146  
Investment, Identifier [Axis]: Winslow Large Cap Growth Fund    
EBP, Schedule of Asset Held for Investment [Line Items]    
Total investments $ 23,163,203