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Commitments and Contingencies (Details) - Westmoreland - NSP-Minnesota $ in Millions | 9 Months Ended
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Sep. 30, 2021 USD ($)
Commitments and Contingencies Disclosure [Abstract] |
Gain (Loss) Related to Litigation Settlement | $ 36
Public Utilities, General Disclosures [Line Items] |
Gain (Loss) Related to Litigation Settlement | $ 36

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- Definition Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=121557415&loc=d3e14326-108349 + Details
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