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Idaho Public Utilities Commission (IPUC) (Details) - IPUC - Tax Cuts and Jobs Act - USD ($) $ in Millions	Mar. 23, 2018	Mar. 12, 2018
Public Utilities, General Disclosures [Line Items]
State corporate income tax rate		7.40%
State corporate income tax rate, current		6.90%
Public utilities, requested rate increase (decrease), amount	$ (5)

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- Definition

State corporate income tax rate prior to TCJA.

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- Definition

State corporate income tax rate, after TCJA.

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- Definition

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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