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WUTC (Details 5) - Natural gas rate proceeding [Member] - WUTC - USD ($) $ in Millions | May 31, 2019 | Mar. 29, 2019 | Mar. 28, 2019
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Public Utilities, General Disclosures [Line Items] |  |  |
Public Utilities, Approved Rate Increase (Decrease), Amount |  |  | $ 48.0
Public utilities, requested rate increase (decrease), amount | $ 1.6 | $ 12.7 |
Public utilities, requested rate increase (decrease), percentage | 0.70% | 5.50% |

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- Definition Amount of public utility's requested rate increase (decrease) with regulatory agency. + References No definition available. + Details
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