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Regulatory Matters (Tables) | 9 Months Ended
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Sep. 30, 2025
Regulated Operations [Abstract] |
Schedule of Regulatory Assets and Liabilities | We had the following regulatory assets and liabilities:
| As of |  | As of |
| September 30, 2025 |  | December 31, 2024 |
| (in millions) |
Regulatory assets |  |  |  |
Winter Storm Uri | $ | 62.1 |  | $ | 109.5 |
Deferred energy and fuel cost adjustments |  | 76.1 |  |  | 62.8 |
Deferred gas cost adjustments |  | 7.5 |  |  | 14.5 |
Gas price derivatives |  | 4.9 |  |  | 2.9 |
Deferred taxes on AFUDC |  | 9.5 |  |  | 8.0 |
Employee benefit plans and related deferred taxes |  | 85.7 |  |  | 89.0 |
Environmental |  | 11.5 |  |  | 10.7 |
Loss on reacquired debt |  | 14.5 |  |  | 15.7 |
Deferred taxes on flow through accounting |  | 93.1 |  |  | 87.7 |
Decommissioning costs |  | 2.4 |  |  | 2.4 |
Other regulatory assets |  | 23.9 |  |  | 24.5 |
Total regulatory assets |  | 391.2 |  |  | 427.7 |
Less current regulatory assets |  | (138.2 | ) |  | (154.8 | )
Regulatory assets, non-current | $ | 253.0 |  | $ | 272.9 |
Regulatory liabilities |  |  |  |
Deferred energy and gas costs | $ | 61.1 |  | $ | 67.8 |
Employee benefit plan costs and related deferred taxes |  | 35.0 |  |  | 36.7 |
Cost of removal |  | 212.0 |  |  | 197.0 |
Excess deferred income taxes |  | 232.4 |  |  | 238.5 |
Colorado renewable energy (a) |  | 30.7 |  |  | 24.1 |
Other regulatory liabilities |  | 5.4 |  |  | 4.6 |
Total regulatory liabilities |  | 576.6 |  |  | 568.7 |
Less current regulatory liabilities |  | (91.9 | ) |  | (94.1 | )
Regulatory liabilities, non-current | $ | 484.7 |  | $ | 474.6 |
(a) Represents Colorado Electric's RESA and CEPR mechanisms, which allow for recovery/repayment of costs, but not a rate of return.

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