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WYPSC (Details 6) - WYPSC - USD ($) | Jul. 16, 2019 | May 23, 2019 | Apr. 08, 2019
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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) |  |

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