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WUTC (Details 6) - Pipeline replacement cost recovery [Member] - WUTC [Member] - USD ($) $ in Millions	Oct. 11, 2018	Jun. 01, 2018
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount		$ 2.3
Public utilities, requested rate increase (decrease), percentage		1.10%
Public Utilities, Approved Rate Increase (Decrease), Amount	$ 2.1
Public utilities, approved rate increase (decrease), percentage	1.00%

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

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- Definition

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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- Definition

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

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- Definition

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

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