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Oregon Public Utility Commission (OPUC) (Details 7) - OPUC [Member] - Pipeline replacement cost recovery [Member]	Sep. 29, 2017 USD ($)
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount	$ 784,000
Public utilities, requested rate increase (decrease), percentage	1.20%

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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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