0000001 - Document - Cover link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS’ EQUITY (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952156 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS link:presentationLink link:calculationLink link:definitionLink 9952157 - Disclosure - General link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Regulatory Matters link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Capitalization link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Lines of Credit and Long-Term Liabilities link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Income Taxes link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Commitments and Contingencies link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Benefit Plans link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Equity Plans link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Segment Reporting link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Subsequent Events link:presentationLink link:calculationLink link:definitionLink 9955511 - Disclosure - General (Policies) link:presentationLink link:calculationLink link:definitionLink 9955512 - Disclosure - General (Tables) link:presentationLink link:calculationLink link:definitionLink 9955513 - Disclosure - Regulatory Matters (Tables) link:presentationLink link:calculationLink link:definitionLink 9955514 - Disclosure - Benefit Plans (Tables) link:presentationLink link:calculationLink link:definitionLink 9955515 - Disclosure - Equity Plans (Tables) link:presentationLink link:calculationLink link:definitionLink 9955516 - Disclosure - Segment Reporting (Tables) link:presentationLink link:calculationLink link:definitionLink 9955517 - Disclosure - General - Schedule of H2O America's Revenue Components (Details) link:presentationLink link:calculationLink link:definitionLink 9955518 - Disclosure - General - Schedule of Nonutility Properties (Details) link:presentationLink link:calculationLink link:definitionLink 9955519 - Disclosure - General - Fair Value Measurement (Details) link:presentationLink link:calculationLink link:definitionLink 9955520 - Disclosure - General - Earnings per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9955521 - Disclosure - Regulatory Matters - Regulatory Assets, Net (Details) link:presentationLink link:calculationLink link:definitionLink 9955522 - Disclosure - Regulatory Matters - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955523 - Disclosure - Capitalization (Details) link:presentationLink link:calculationLink link:definitionLink 9955524 - Disclosure - Lines of Credit and Long-Term Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9955525 - Disclosure - Income Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9955526 - Disclosure - Commitments and Contingencies (Details) link:presentationLink link:calculationLink link:definitionLink 9955527 - Disclosure - Benefit Plans - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955528 - Disclosure - Benefit Plans - Schedule of Net Benefit Costs (Details) link:presentationLink link:calculationLink link:definitionLink 9955529 - Disclosure - Equity Plans - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955530 - Disclosure - Equity Plans - Compensation Costs Charged to Income, by Award Type and Proceeds from ESPP (Details) link:presentationLink link:calculationLink link:definitionLink 9955531 - Disclosure - Segment Reporting - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Segment Reporting - Reportable Segment and Other Business Activities (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Subsequent Events (Details) link:presentationLink link:calculationLink link:definitionLink