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Regulatory Matters (Tables) | 3 Months Ended
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Mar. 31, 2021
Regulatory Assets and Liabilities Disclosure [Abstract] |
Schedule of COVID-19 Regulatory Impact | The ongoing impacts of these approvals or directives are described in the table below:
Jurisdiction | Moratorium in Place? | Regulatory Asset balance as of March 31, 2021 (in millions) | Deferred COVID-19 Costs
Columbia of Ohio | No | $ | 2.0 |  | Incremental operation and maintenance expenses
NIPSCO | No | $ | 12.0 |  | Incremental bad debt expense and the costs to implement the requirements of the COVID-19 related order
Columbia of Pennsylvania | No | $ | 7.1 |  | Incremental bad debt expense incurred since March 13, 2020 above levels currently in rates
Columbia of Virginia | Yes | $ | 0.1 |  | Incremental incurred costs, subject to an earnings test review
Columbia of Maryland | No | $ | 1.1 |  | Incremental costs (including incremental bad debt expense) incurred to ensure that customers have essential utility service during the state of emergency in Maryland. Such incremental costs must be offset by any benefit received in connection with the pandemic

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