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Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Cost of removal Cost of Removal [Member] Cost of Removal Administrative and general Administrative and general General and Administrative Expense Sale of stock (in usd per share) Sale of Stock, Price Per Share Receivable period for noncurrent cash proceeds receivable form legal settlement Loss Contingency, Receivable, Noncurrent Period Loss Contingency, Receivable, Noncurrent Period Total regulatory liabilities Regulatory Liability Production expenses: Water Production Costs [Abstract] Water Production Costs [Abstract] Adjustment to Compensation: Adjustment to Compensation [Axis] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest, net of amounts capitalized Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Regulatory Matters Schedule of Regulatory Assets and Liabilities [Text Block] Name Measure Name Income Taxes Income Tax Disclosure [Text Block] Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Settlement payable to contract operators Settlement Liabilities, Current Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Name Trading Arrangement, Individual Name Schedule of Regulatory Assets, Net Schedule of Regulatory Assets [Table Text Block] Cash and cash equivalents Cash and Cash Equivalent Variable interest entity, ownership percentage Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage Company Selected Measure Amount Company Selected Measure Amount Total number of outstanding (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding, Number Depreciation and amortization Depreciation, Depletion and Amortization Issuance of restricted and deferred stock units (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Quadvest Retail Quadvest Retail [Member] Quadvest Retail PFAS Contamination Legal Settlements PFAS Contamination Legal Settlements [Member] PFAS Contamination Legal Settlements Current assets: Assets, Current [Abstract] Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Total production expenses Production expenses Water Production Costs Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Other Other Regulatory Assets [Member] Other Regulatory Assets [Member] Proceeds from sale of real estate investments and release of escrow deposit Proceeds From Sale, Real Estate, Held-For-Investment And Release Of Escrow Deposit Proceeds From Sale, Real Estate, Held-For-Investment And Release Of Escrow Deposit Provision for income taxes Income tax expense Provision (benefit) for income taxes Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] Net change in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Estimated service lives of assets Public Utilities, Property, Plant and Equipment, Common, Useful Life Receipts of advances and contributions in aid of construction Receipts Of Advances And Contributions In Aid Of Construction Receipts Of Advances And Contributions In Aid Of Construction Proceeds from legal settlements Proceeds from Legal Settlements Tranche Three Share-Based Payment Arrangement, Tranche Three [Member] Net income Net income Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Other Services Segment Reporting, Reconciling Item, Excluding Corporate Nonsegment [Member] Tranche Two Share-Based Payment Arrangement, Tranche Two [Member] Restatement Determination Date: Restatement Determination Date [Axis] Restricted stock and deferred restricted stock Restricted Stock And Deferred Restricted Stock [Member] Restricted Stock and Deferred Restricted Stock [Member] Refunds of advances for construction Repayments Of Advances For Construction, Financing Activities Repayments Of Advances For Construction, Financing Activities Amortization of actuarial gain Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss) Rate of compensation increase Defined Benefit Plan, Rate Of Compensation Increase Defined Benefit Plan, Rate Of Compensation Increase Accounts receivable and accrued unbilled utility revenue Increase (Decrease) in Receivables Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]