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Regulatory Matters - Summary of Utilities Rate Plans (O&R New York-Electric) (Details) - USD ($) | 1 Months Ended | 12 Months Ended | 24 Months Ended | 36 Months Ended |
--- | --- | --- | --- | --- | ---
Jan. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Oct. 31, 2017 | Dec. 31, 2021 | Oct. 31, 2018 | Dec. 31, 2022
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Deferred revenues |  | $ 41,000,000 | $ 17,000,000 | $ 20,000,000 | $ 87,000,000 |  |  |  |  |  |
Deferred revenues |  | $ 599,000,000 | 599,000,000 |  |  |  |  |  |  |  |
NYSPSC |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of total consolidated revenues |  | 15.00% |  |  |  |  |  |  |  |  |
Percentage of debt to total consolidated debt |  | 20.00% |  |  |  |  |  |  |  |  |
Maximum | NYSPSC |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Percentage of total consolidated revenues |  | 15.00% |  |  |  |  |  |  |  |  |
O&R |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Actual earnings adjustment mechanism incentives |  | $ 3,000,000 |  |  |  |  |  |  |  |  |
O&R | Electric |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Deferred revenues |  |  |  |  |  | $ 6,300,000 |  |  |  |  |
Deferred revenues |  | 6,000,000 | 100,000 | 500,000 | 11,200,000 |  |  |  |  |  |
Negative revenue adjustments |  |  | 0 | 0 | 0 | 1,250,000 |  |  |  |  |
Deferral of net increase (decrease) to regulatory assets |  | 30,300,000 | 4,300,000 | 5,000,000 | 3,200,000 | 7,400,000 | $ 300,000 |  |  |  |
Net utility plant reconciliations |  |  | 1,400,000 | (1,900,000) | (1,900,000) | 2,200,000 |  |  |  |  |
Authorized return on common equity (percent) |  |  |  |  |  |  |  | 900.00% |  |  |
Earnings sharing (percent) |  |  |  |  |  |  |  | 9.60% |  |  |
Earnings sharing, threshold limit |  |  |  | 300,000 | 6,100,000 |  |  |  |  |  |
Common Equity Ratio, Percentage |  |  |  |  |  |  |  | 4800.00% |  |  |
Deferred storm and property reserve deficiency, noncurrent |  |  |  |  |  |  |  | $ 59,300,000 |  |  |
Deferred storm and property reserve deficiency, recovery period |  |  |  |  |  |  |  | 5 years |  |  |
Deferred storm and property reserve deficiency not recovered |  |  |  |  |  |  |  | $ 1,000,000 |  |  |
Deferred Regulatory Asset (Liability) |  | 400,000 |  |  |  |  |  |  |  |  |
O&R | Electric | NYSPSC | Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common Equity Ratio, Percentage | 50.00% |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount | $ 24,500,000 |  |  |  |  |  |  |  |  |  |
Return on common equity (percent) | 9.50% |  |  |  |  |  |  |  |  |  |
O&R | Electric | Property Tax and Interest Rate Reconciliations |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Regulatory assets not recoverable |  |  |  |  |  |  |  | 4,000,000 |  |  |
O&R | Electric | Year 1 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  | 9,300,000 |  |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  | (8,500,000) |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  | 928,000,000 |  |  |
Average rate base |  |  |  |  |  |  |  | $ 763,000,000 |  |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  | 7.10% |  |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  | 10.80% |  |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  | 5.42% |  |  |
Deferred storm and property reserve deficiency, noncurrent |  |  |  |  |  |  |  | $ 11,850,000 |  |  |
Rate exclusion amount with balance below regulatory threshold |  |  |  |  |  |  |  | 1,000,000 |  |  |
O&R | Electric | Year 1 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  | 4,000,000 |  |  |
O&R | Electric | Year 2 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  | 8,800,000 |  |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  | (9,400,000) |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  | 970,000,000 |  |  |
Average rate base |  |  |  |  |  |  |  | $ 805,000,000 |  |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  | 7.06% |  |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  | 9.70% |  |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  | 5.35% |  |  |
Rate exclusion amount with balance below regulatory threshold |  |  |  |  |  |  |  | $ 9,000,000 |  |  |
O&R | Electric | Year 2 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  | 4,000,000 |  |  |
O&R | Electric | Year 3 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  | 0 |  |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  | 0 |  |  |
Average rate base |  |  |  |  |  |  |  | $ 805,000,000 |  |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  | 7.06% |  |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  | 7.20% |  |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  | 5.35% |  |  |
O&R | Electric | Year 3 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  | $ 4,000,000 |  |  |
O&R | Electric | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Authorized return on common equity (percent) |  |  |  |  |  |  |  |  | 900.00% |  |
Earnings sharing (percent) |  |  |  |  |  |  |  |  |  |  | 9.60%
Common Equity Ratio, Percentage |  |  |  |  |  |  |  |  | 4800.00% |  |
Deferrals for property taxes limitation from rates (percent) |  |  |  |  |  |  |  |  | 90.00% |  |
O&R | Electric | Scenario, Forecast | Year 1 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | $ 13,400,000 |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,500,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 3,600,000 |  |
Potential incentive if target is met, related to service terminations |  |  |  |  |  |  |  |  | 500,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 878,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.97% |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  | 9.60% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.17% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ 8,600,000 |  |
Deferral, annual maximum (not more than) (percent) |  |  |  |  |  |  |  |  | 10.00% |  |
O&R | Electric | Scenario, Forecast | Year 1 | Electric average excluding AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | $ 1,008,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 1 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 48,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 1 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | 4,400,000 |  |
O&R | Electric | Scenario, Forecast | Year 2 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | 8,000,000.0 |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,500,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 4,000,000.0 |  |
Potential incentive if target is met, related to service terminations |  |  |  |  |  |  |  |  | 500,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 906,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.96% |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  | 8.76% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.14% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ 12,100,000 |  |
Deferral, annual maximum (not more than) (percent) |  |  |  |  |  |  |  |  | 7.50% |  |
O&R | Electric | Scenario, Forecast | Year 2 | Electric average excluding AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | $ 1,032,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 2 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 58,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 2 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | 4,400,000 |  |
O&R | Electric | Scenario, Forecast | Year 3 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | 5,800,000 |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,500,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 4,200,000 |  |
Potential incentive if target is met, related to service terminations |  |  |  |  |  |  |  |  | 500,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 948,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.96% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.14% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ 12,200,000 |  |
Deferral, annual maximum (not more than) (percent) |  |  |  |  |  |  |  |  | 5.00% |  |
O&R | Electric | Scenario, Forecast | Year 3 | Electric average excluding AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | $ 1,083,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 3 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 61,000,000 |  |
O&R | Electric | Scenario, Forecast | Year 3 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | 4,500,000 |  |
O&R | Gas |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Deferred revenues |  |  | 6,300,000 | 1,700,000 | 6,200,000 |  |  |  |  |  |
Deferred revenues |  | 500,000 | 800,000 |  |  | 800,000 |  |  |  |  |
Negative revenue adjustments |  | 200,000 | 100,000 | 0 | 0 | $ 0 |  |  |  |  |
Authorized return on common equity (percent) |  |  |  |  |  |  |  |  |  | 9.00% |
Earnings sharing (percent) |  |  |  |  |  |  |  |  |  | 9.60% |
Earnings sharing, threshold limit |  |  |  | $ 200,000 | $ 4,000,000 |  |  |  |  |  |
Common Equity Ratio, Percentage |  |  |  |  |  |  |  |  |  | 4800.00% |
Deferred Regulatory Asset (Liability) |  |  | 400,000 |  |  |  |  |  |  |  |
O&R | Gas | NYSPSC | Subsequent Event |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Common Equity Ratio, Percentage | 50.00% |  |  |  |  |  |  |  |  |  |
Requested rate increase (decrease), amount | $ 9,800,000 |  |  |  |  |  |  |  |  |  |
Return on common equity (percent) | 9.50% |  |  |  |  |  |  |  |  |  |
O&R | Gas | Property Tax and Interest Rate Reconciliations |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Regulatory assets not recoverable |  |  |  |  |  |  |  |  |  | $ 14,000,000 |
O&R | Gas | Year 1 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  |  | 16,400,000 |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  |  | (1,700,000) |
Net utility plant reconciliations |  |  |  |  |  |  |  |  |  | 492,000,000 |
Average rate base |  |  |  |  |  |  |  |  |  | $ 366,000,000 |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  |  | 7.10% |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  |  | 11.20% |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  |  | 5.42% |
Rate exclusion amount with balance below regulatory threshold |  |  |  |  |  |  |  |  |  | $ 500,000 |
O&R | Gas | Year 1 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  |  | 3,700,000 |
O&R | Gas | Year 2 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  |  | 16,400,000 |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  |  | (2,100,000) |
Net utility plant reconciliations |  |  |  |  |  |  |  |  |  | 518,000,000 |
Average rate base |  |  |  |  |  |  |  |  |  | $ 391,000,000 |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  |  | 7.06% |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  |  | 9.70% |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  |  | 5.35% |
Rate exclusion amount with balance below regulatory threshold |  |  |  |  |  |  |  |  |  | $ 4,200,000 |
O&R | Gas | Year 2 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  |  | 4,700,000 |
O&R | Gas | Year 3 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  |  | 5,800,000 |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  |  | (2,500,000) |
Net utility plant reconciliations |  |  |  |  |  |  |  |  |  | 546,000,000 |
Average rate base |  |  |  |  |  |  |  |  |  | $ 417,000,000 |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  |  | 7.06% |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  |  | 8.10% |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  |  | 5.35% |
Rate exclusion amount with balance below regulatory threshold |  |  |  |  |  |  |  |  |  | $ 7,200,000 |
O&R | Gas | Year 3 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  |  | $ 4,900,000 |
O&R | Gas | Scenario, Forecast |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | $ 300,000 |  |
Authorized return on common equity (percent) |  |  |  |  |  |  |  |  | 9.00% |  |
Earnings sharing (percent) |  |  |  |  |  |  |  |  |  |  | 9.60%
Common Equity Ratio, Percentage |  |  |  |  |  |  |  |  | 4800.00% |  |
O&R | Gas | Scenario, Forecast | Year 1 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | $ (7,500,000) |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,800,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 1,200,000 |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 593,000,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 454,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.97% |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  | 8.90% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.17% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ (5,900,000) |  |
O&R | Gas | Scenario, Forecast | Year 1 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 20,000,000 |  |
O&R | Gas | Scenario, Forecast | Year 1 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | 5,500,000 |  |
O&R | Gas | Scenario, Forecast | Year 2 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | 3,600,000 |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,800,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 1,300,000 |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 611,000,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 476,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.96% |  |
Actual return on common equity (percent) |  |  |  |  |  |  |  |  | 9.58% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.14% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ 1,000,000.0 |  |
O&R | Gas | Scenario, Forecast | Year 2 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 24,000,000 |  |
O&R | Gas | Scenario, Forecast | Year 2 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | 5,700,000 |  |
O&R | Gas | Scenario, Forecast | Year 3 |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Base rate changes |  |  |  |  |  |  |  |  | 700,000 |  |
Amortization to income of net regulatory assets |  |  |  |  |  |  |  |  | (1,800,000) |  |
Potential earnings adjustment mechanism incentives |  |  |  |  |  |  |  |  | 1,300,000 |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 632,000,000 |  |
Average rate base |  |  |  |  |  |  |  |  | $ 498,000,000 |  |
Weighted average cost of capital (after-tax) (percent) |  |  |  |  |  |  |  |  | 6.96% |  |
Cost of long-term debt (percent) |  |  |  |  |  |  |  |  | 5.14% |  |
Requested rate increase (decrease), amount |  |  |  |  |  |  |  |  | $ 1,000,000.0 |  |
O&R | Gas | Scenario, Forecast | Year 3 | AMI |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Net utility plant reconciliations |  |  |  |  |  |  |  |  | 25,000,000 |  |
O&R | Gas | Scenario, Forecast | Year 3 | Maximum |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Potential penalties (annually) |  |  |  |  |  |  |  |  | $ 6,000,000.0 |  |
Energy Efficiency | O&R | Electric |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Actual earnings adjustment mechanism incentives |  | 2,600,000 |  |  |  |  |  |  |  |  |
Energy Efficiency | O&R | Gas |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Actual earnings adjustment mechanism incentives |  | 300,000 |  |  |  |  |  |  |  |  |
Service Termination | O&R | Electric |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Actual earnings adjustment mechanism incentives |  | 500,000 | 200,000 |  |  |  |  |  |  |  |
Service Termination | O&R | Gas |  |  |  |  |  |  |  |  |  |  |
Public Utilities, General Disclosures [Line Items] |  |  |  |  |  |  |  |  |  |  |
Actual earnings adjustment mechanism incentives |  | $ 500,000 | $ 700,000 |  |  |  |  |  |  |  |

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