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REGULATION - REGULATORY FILINGS (Details) - Natural Gas Distribution - USD ($) $ in Millions | Dec. 28, 2018 | Dec. 18, 2018
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Energy Efficiency EE |  |
Schedule of Regulatory Filings [Line Items] |  |
Approved rate increase (decrease), amount |  | $ (8.8)
BGSS/CIP Filing |  |
Schedule of Regulatory Filings [Line Items] |  |
Requested customer refunds, amount | $ 10.9 |

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