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

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Public Utilities, Proposed One-Time Increase (Decrease) to Customers, Amount

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

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WYPSC (Details 6) - WYPSC - USD ($)	Jul. 16, 2019	May 23, 2019	Apr. 08, 2019
Natural gas rate proceeding [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%
Tax Cuts and Jobs Act [Member] \| Electric rate proceeding
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%)
Public Utilities, Approved One-Time Increase (Decrease) to Customers, Amount			$ (1,600,000)
Subsequent Event [Member] \| Tax Cuts and Jobs Act [Member] \| Natural gas rate proceeding [Member]
Public Utilities, General Disclosures [Line Items]
Public Utilities, Proposed One-Time Increase (Decrease) to Customers, Amount	$ (190,000)