Public Utilities, Approved One-Time Increase (Decrease) to Customers, Amount [Line Items]

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

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- Definition

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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- Definition

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

+ References

No definition available.

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WYPSC (Details 6) - WYPSC - Montana-Dakota Utilities Co. [Member] - USD ($)	Nov. 01, 2019	Jul. 25, 2019	May 23, 2019	May 01, 2019
Electricity [Member] \| Tax Cuts and Jobs Act [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Approved Rate Increase (Decrease), Amount				$ (1,100,000)
Public Utilities, Approved Rate Increase (Decrease), Percentage				(4.20%)
Approved Customer Refunds		$ (1,600,000)
Gas Distribution [Member] \| Pending Rate Case [Member]
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%
Gas Distribution [Member] \| Tax Cuts and Jobs Act [Member] \| Subsequent Event [Member]
Public Utilities, General Disclosures [Line Items]
Approved Customer Refunds	$ (200,000)