WYPSC (Details 4) - Gas Distribution [Member] - WYPSC - Montana-Dakota Utilities Co. [Member] - USD ($)	Mar. 01, 2020	May 23, 2019
Public Utilities, General Disclosures [Line Items]
Public Utilities, Requested Rate Increase (Decrease), Amount		$ 1,100,000
Public Utilities, Requested Rate Increase (Decrease), Percentage		7.00%
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 830,000
Public Utilities, Approved Rate Increase (Decrease), Percentage	5.50%

Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved rate increase (decrease) by regulatory agency.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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No definition available.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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No definition available.

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