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Regulatory Matters (Schedule of COVID-19 Regulatory Impact) (Details) $ in Millions | Mar. 31, 2021 USD ($)
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Incremental O&M - COVID | Columbia Of Ohio |
Regulated Operations |
Regulatory Assets | $ 2.0
Incremental O&M - COVID | Columbia Of Virginia |
Regulated Operations |
Regulatory Assets | 0.1
Incremental O&M and Bad Debt - COVID | NIPSCO |
Regulated Operations |
Regulatory Assets | 12.0
Incremental O&M and Bad Debt - COVID | Columbia Of Maryland |
Regulated Operations |
Regulatory Assets | 1.1
Incremental Bad Debt - COVID | Columbia Of Pennsylvania |
Regulated Operations |
Regulatory Assets | $ 7.1

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- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
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