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v3.25.3

Summary of Significant Accounting Policies (Tables) | 9 Months Ended
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Sep. 30, 2025
Components of Gas and Electric Operating Revenue | In the following tables, revenue is classified by the types of goods/services rendered and market/customer type.
|  | Three Months Ended September 30, 2025 |
Electric and Gas Operating Revenues (millions): |  | Electric |  |  | Gas |  |  | Total |
Billed and Unbilled Revenue: |  |  |  |  |  |  |  |  |
Residential |  | $ | 33.6 |  |  | $ | 10.1 |  |  | $ | 43.7 |
Commercial and Industrial |  |  | 25.4 |  |  |  | 17.5 |  |  |  | 42.9 |
Other |  |  | 2.6 |  |  |  | 1.4 |  |  |  | 4.0 |
Total Billed and Unbilled Revenue |  |  | 61.6 |  |  |  | 29.0 |  |  |  | 90.6 |
Rate Adjustment Mechanism Revenue |  |  | 2.7 |  |  |  | 7.8 |  |  |  | 10.5 |
Total Electric and Gas Operating Revenues |  | $ | 64.3 |  |  | $ | 36.8 |  |  | $ | 101.1 |
|  | Three Months Ended September 30, 2024 |
Electric and Gas Operating Revenues (millions): |  | Electric |  |  | Gas |  |  | Total |
Billed and Unbilled Revenue: |  |  |  |  |  |  |  |  |
Residential |  | $ | 37.4 |  |  | $ | 8.9 |  |  | $ | 46.3 |
Commercial and Industrial |  |  | 27.4 |  |  |  | 15.2 |  |  |  | 42.6 |
Other |  |  | 2.7 |  |  |  | 1.2 |  |  |  | 3.9 |
Total Billed and Unbilled Revenue |  |  | 67.5 |  |  |  | 25.3 |  |  |  | 92.8 |
Rate Adjustment Mechanism Revenue |  |  | (5.0 | ) |  |  | 5.1 |  |  |  | 0.1 |
Total Electric and Gas Operating Revenues |  | $ | 62.5 |  |  | $ | 30.4 |  |  | $ | 92.9 |
|  | Nine Months Ended September 30, 2025 |
Electric and Gas Operating Revenues (millions): |  | Electric |  |  | Gas |  |  | Total |
Billed and Unbilled Revenue: |  |  |  |  |  |  |  |  |
Residential |  | $ | 90.2 |  |  | $ | 86.9 |  |  | $ | 177.1 |
Commercial and Industrial |  |  | 69.9 |  |  |  | 117.9 |  |  |  | 187.8 |
Other |  |  | 9.3 |  |  |  | 11.3 |  |  |  | 20.6 |
Total Billed and Unbilled Revenue |  |  | 169.4 |  |  |  | 216.1 |  |  |  | 385.5 |
Rate Adjustment Mechanism Revenue |  |  | 6.1 |  |  |  | (17.1 | ) |  |  | (11.0 | )
Total Electric and Gas Operating Revenues |  | $ | 175.5 |  |  | $ | 199.0 |  |  | $ | 374.5 |
|  | Nine Months Ended September 30, 2024 |
Electric and Gas Operating Revenues (millions): |  | Electric |  |  | Gas |  |  | Total |
Billed and Unbilled Revenue: |  |  |  |  |  |  |  |  |
Residential |  | $ | 108.4 |  |  | $ | 68.3 |  |  | $ | 176.7 |
Commercial and Industrial |  |  | 81.7 |  |  |  | 97.4 |  |  |  | 179.1 |
Other |  |  | 7.2 |  |  |  | 6.9 |  |  |  | 14.1 |
Total Billed and Unbilled Revenue |  |  | 197.3 |  |  |  | 172.6 |  |  |  | 369.9 |
Rate Adjustment Mechanism Revenue |  |  | (4.8 | ) |  |  | 2.2 |  |  |  | (2.6 | )
Total Electric and Gas Operating Revenues |  | $ | 192.5 |  |  | $ | 174.8 |  |  | $ | 367.3 |
Allowance for Doubtful Accounts Included in Accounts Receivable Net | The Allowance for Doubtful Accounts as of September 30, 2025, September 30, 2024 and December 31, 2024, was as follows:
|  | September 30, |  |  | December 31, |
(millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Allowance for Doubtful Accounts |  | $ | 1.2 |  |  | $ | 2.0 |  |  | $ | 2.4 |
Components of Accrued Revenue | The following table shows the components of Accrued Revenue as of September 30, 2025, September 30, 2024 and December 31, 2024.
|  | September 30, |  |  | December 31, |
Accrued Revenue (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Regulatory Assets – Current |  | $ | 60.5 |  |  | $ | 61.3 |  |  | $ | 70.1 |
Unbilled Revenues, net |  |  | 4.2 |  |  |  | 4.1 |  |  |  | 7.3 |
Total Accrued Revenue |  | $ | 64.7 |  |  | $ | 65.4 |  |  | $ | 77.4 |
Components of Exchange Gas Receivable | The following table shows the components of Exchange Gas Receivable as of September 30, 2025, September 30, 2024 and December 31, 2024.
|  | September 30, |  |  | December 31, |
Exchange Gas Receivable (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Northern Utilities |  | $ | 12.8 |  |  | $ | 8.8 |  |  | $ | 6.0 |
Fitchburg |  |  | 0.7 |  |  |  | 0.5 |  |  |  | 0.4 |
Bangor |  |  | 1.6 |  |  |  | — |  |  |  | — |
Total Exchange Gas Receivable |  | $ | 15.1 |  |  | $ | 9.3 |  |  | $ | 6.4 |
Components of Gas Inventory | The following table shows the components of Gas Inventory as of September 30, 2025, September 30, 2024 and December 31, 2024.
|  | September 30, |  |  | December 31, |
Gas Inventory (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Natural Gas |  | $ | 0.4 |  |  | $ | 0.2 |  |  | $ | 0.2 |
Propane |  |  | 0.4 |  |  |  | 0.4 |  |  |  | 0.4 |
Liquefied Natural Gas & Other |  |  | 0.5 |  |  |  | 0.5 |  |  |  | 0.5 |
Total Gas Inventory |  | $ | 1.3 |  |  | $ | 1.1 |  |  | $ | 1.1 |
Regulatory Assets | The Company currently receives recovery in rates or expects to receive recovery of these hardship accounts in future rate cases.
|  | September 30, |  |  | December 31, |
Regulatory Assets consist of the following (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Retirement Benefits |  | $ | 19.1 |  |  | $ | 26.2 |  |  | $ | 14.4 |
Energy Supply and Other Rate Adjustment Mechanisms |  |  | 55.4 |  |  |  | 56.5 |  |  |  | 65.4 |
Deferred Storm Charges |  |  | 7.5 |  |  |  | 8.9 |  |  |  | 8.3 |
Environmental |  |  | 10.6 |  |  |  | 6.3 |  |  |  | 9.4 |
Income Taxes |  |  | 0.5 |  |  |  | 0.5 |  |  |  | 0.4 |
Other Deferred Charges |  |  | 12.5 |  |  |  | 12.4 |  |  |  | 14.1 |
Total Regulatory Assets |  |  | 105.6 |  |  |  | 110.8 |  |  |  | 112.0 |
Less: Current Portion of Regulatory Assets(1) |  |  | 60.5 |  |  |  | 61.3 |  |  |  | 70.1 |
Regulatory Assets – noncurrent |  | $ | 45.1 |  |  | $ | 49.5 |  |  | $ | 41.9 |
Reflects amounts included in the Accrued Revenue on the Company’s Consolidated Balance Sheets.
Regulatory Liabilities |
|  | September 30, |  |  | December 31, |
Regulatory Liabilities consist of the following (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Income Taxes (Note 8) |  | $ | 48.8 |  |  | $ | 50.0 |  |  | $ | 50.4 |
Rate Adjustment Mechanisms & Other |  |  | 15.5 |  |  |  | 18.7 |  |  |  | 13.6 |
Retirement Benefits |  |  | 6.3 |  |  |  | — |  |  |  | — |
Total Regulatory Liabilities |  |  | 70.6 |  |  |  | 68.7 |  |  |  | 64.0 |
Less: Current Portion of Regulatory Liabilities |  |  | 18.4 |  |  |  | 22.4 |  |  |  | 17.2 |
Regulatory Liabilities – noncurrent |  | $ | 52.2 |  |  | $ | 46.3 |  |  | $ | 46.8 |
Fair Value of Marketable Securities | Changes in the fair value of these investments are recorded in Other Expense, Net.
|  | September 30, |  |  | December 31, |
Fair Value of Marketable Securities (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Money Market Funds |  | $ | 1.8 |  |  | $ | 1.8 |  |  | $ | 2.5 |
Fixed Income Funds |  |  | 4.3 |  |  |  | 4.0 |  |  |  | 3.8 |
Total Marketable Securities |  | $ | 6.1 |  |  | $ | 5.8 |  |  | $ | 6.3 |
Components of Energy Supply Obligations | The following discussion and table summarize the nature and amounts of the items recorded as Energy Supply Obligations (current portion) and Other Noncurrent Liabilities (noncurrent portion) on the Company’s Consolidated Balance Sheets.
|  | September 30, |  |  | December 31, |
Energy Supply Obligations (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Current: |  |  |  |  |  |  |  |  |
Exchange Gas Obligation |  | $ | 14.4 |  |  | $ | 8.8 |  |  | $ | 6.0 |
Renewable Energy Portfolio Standards |  |  | 2.6 |  |  |  | 4.0 |  |  |  | 4.0 |
Total Energy Supply Obligations |  | $ | 17.0 |  |  | $ | 12.8 |  |  | $ | 10.0 |
Deferred Compensation Plan [Member] |
Fair Value of Marketable Securities | Changes in the fair value of these investments are recorded in Other Expense, Net.
|  | September 30, |  |  | December 31, |
Fair Value of Marketable Securities (millions) |  | 2025 |  |  | 2024 |  |  | 2024 |
Equity Funds |  | $ | 2.9 |  |  | $ | 1.9 |  |  | $ | 2.0 |
Fixed Income Funds |  |  | 0.2 |  |  |  | 0.1 |  |  |  | 0.1 |
Money Market Funds |  |  | 0.1 |  |  |  | 0.1 |  |  |  | 0.1 |
Total Marketable Securities |  | $ | 3.2 |  |  | $ | 2.1 |  |  | $ | 2.2 |

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