Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Nature of Operations: American States Water Company (“AWR”) is the parent company of Golden State Water Company (“GSWC”), Bear Valley Electric Service Inc. (“BVES”), and American States Utility Services, Inc. (“ASUS”) (and its subsidiaries, Fort Bliss Water Services Company (“FBWS”), Old Dominion Utility Services, Inc. (“ODUS”), Terrapin Utility Services, Inc. (“TUS”), Palmetto State Utility Services, Inc. (“PSUS”), Old North Utility Services, Inc. (“ONUS”), Emerald Coast Utility Services, Inc. (“ECUS”), Fort Riley Utility Services, Inc. (“FRUS”), Bay State Utility Services LLC (“BSUS”), and Patuxent River Utility Services LLC (“PRUS”)). AWR and its subsidiaries may be collectively referred to as “the Company.” AWR, through its wholly owned subsidiaries, serves over one million people in ten states. GSWC and BVES are both California public utilities. GSWC engages in the purchase, production, distribution and sale of water throughout California serving approximately 265,100 customer connections. BVES distributes electricity in several San Bernardino County mountain communities in California serving approximately 24,900 customer connections. The California Public Utilities Commission (“CPUC”) regulates GSWC’s and BVES’s businesses in matters including properties, rates, services, facilities, and transactions between GSWC, BVES, and their affiliates. ASUS, through its wholly owned subsidiaries, operates, maintains and performs construction activities (including renewal and replacement capital work) on water and/or wastewater systems at various U.S. military bases pursuant to initial 50-year firm fixed-price contracts with the U.S. government and one 15-year contract with the U.S. government. These contracts are subject to annual economic price adjustments and modifications for changes in circumstances, changes in laws and regulations, and additions to the contract value for new construction of facilities at the military bases. ASUS also from time to time performs construction services on military bases as a subcontractor. There is no direct regulatory oversight by the CPUC over AWR or the operations, rates or services provided by ASUS or any of its wholly owned subsidiaries. Basis of Presentation: The consolidated financial statements and notes hereto are presented in a combined report filed by two separate Registrants: AWR and GSWC. References in this report to “Registrant” are to AWR and GSWC, collectively, unless otherwise specified. AWR owns all of the outstanding common shares of GSWC, BVES and ASUS. ASUS owns all of the outstanding equity of its subsidiaries. The consolidated financial statements of AWR include the accounts of AWR and its subsidiaries. These financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Intercompany transactions and balances have been eliminated in AWR’s consolidated financial statements. The consolidated financial statements included herein have been prepared by Registrant, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The December 31, 2025 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The preparation of the consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. In the opinion of management, all adjustments consisting of normal, recurring items, and estimates necessary for a fair statement of the results for the interim periods have been made. It is suggested that these consolidated financial statements be read in conjunction with the consolidated financial statements and the notes thereto included in the Form 10-K for the year ended December 31, 2025 filed with the SEC. Related Party and Intercompany Transactions: GSWC, BVES and ASUS provide and/or receive various support services to and from their parent, AWR, and among themselves. GSWC allocates certain corporate office administrative and general costs to its affiliates, BVES and ASUS, using allocation factors approved by the CPUC. GSWC allocated corporate office administrative and general costs to BVES of $1.1 million and $1.0 million during the three month periods ended March 31, 2026 and 2025, respectively. GSWC also allocated corporate office administrative and general costs to ASUS of approximately $1.7 million and $1.6 million during the three month periods ended March 31, 2026 and 2025, respectively. When necessary, AWR will make capital contributions to its regulated utilities in order to maintain the CPUC-authorized capital structure. Recent Accounting Pronouncements Not Yet Adopted: In November 2024, the FASB issued Accounting Standards Update 2024-03, (Disaggregation of Income Statement Expenses) requiring public entities to disclose additional information about specific expense categories in the notes to the financial statements on an interim and annual basis. The guidance will be effective for fiscal years beginning after December 15, 2026, and for interim periods beginning after December 15, 2027, with early adoption permitted. Registrant is currently evaluating the impact of adopting this standard.

Nature of Operations: American States Water Company (“AWR”) is the parent company of Golden State Water Company (“GSWC”), Bear Valley Electric Service Inc. (“BVES”), and American States Utility Services, Inc. (“ASUS”) (and its subsidiaries, Fort Bliss Water Services Company (“FBWS”), Old Dominion Utility Services, Inc. (“ODUS”), Terrapin Utility Services, Inc. (“TUS”), Palmetto State Utility Services, Inc. (“PSUS”), Old North Utility Services, Inc. (“ONUS”), Emerald Coast Utility Services, Inc. (“ECUS”), Fort Riley Utility Services, Inc. (“FRUS”), Bay State Utility Services LLC (“BSUS”), and Patuxent River Utility Services LLC (“PRUS”)). AWR and its subsidiaries may be collectively referred to as “the Company.” AWR, through its wholly owned subsidiaries, serves over one million people in ten states.

GSWC and BVES are both California public utilities. GSWC engages in the purchase, production, distribution and sale of water throughout California serving approximately 265,100 customer connections. BVES distributes electricity in several San Bernardino County mountain communities in California serving approximately 24,900 customer connections. The California Public Utilities Commission (“CPUC”) regulates GSWC’s and BVES’s businesses in matters including properties, rates, services, facilities, and transactions between GSWC, BVES, and their affiliates.

ASUS, through its wholly owned subsidiaries, operates, maintains and performs construction activities (including renewal and replacement capital work) on water and/or wastewater systems at various U.S. military bases pursuant to initial 50-year firm fixed-price contracts with the U.S. government and one 15-year contract with the U.S. government. These contracts are subject to annual economic price adjustments and modifications for changes in circumstances, changes in laws and regulations, and additions to the contract value for new construction of facilities at the military bases. ASUS also from time to time performs construction services on military bases as a subcontractor.

Basis of Presentation: The consolidated financial statements and notes hereto are presented in a combined report filed by two separate Registrants: AWR and GSWC. References in this report to “Registrant” are to AWR and GSWC, collectively, unless otherwise specified. AWR owns all of the outstanding common shares of GSWC, BVES and ASUS. ASUS owns all of the outstanding equity of its subsidiaries. The consolidated financial statements of AWR include the accounts of AWR and its subsidiaries. These financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”). Intercompany transactions and balances have been eliminated in AWR’s consolidated financial statements.

The consolidated financial statements included herein have been prepared by Registrant, without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). The December 31, 2025 condensed consolidated balance sheet data was derived from audited financial statements but does not include all disclosures required by GAAP. The preparation of the consolidated financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. In the opinion of management, all adjustments consisting of normal, recurring items, and estimates necessary for a fair statement of the results for the interim periods have been made. It is suggested that these consolidated financial statements be read in conjunction with the consolidated financial statements and the notes thereto included in the Form 10-K for the year ended December 31, 2025 filed with the SEC.

Related Party and Intercompany Transactions: GSWC, BVES and ASUS provide and/or receive various support services to and from their parent, AWR, and among themselves. GSWC allocates certain corporate office administrative and general costs to its affiliates, BVES and ASUS, using allocation factors approved by the CPUC. GSWC allocated corporate office administrative and general costs to BVES of $1.1 million and $1.0 million during the three month periods ended March 31, 2026 and 2025, respectively. GSWC also allocated corporate office administrative and general costs to ASUS of approximately $1.7 million and $1.6 million during the three month periods ended March 31, 2026 and 2025, respectively.