Colstrip 4 Rate Of Return

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- Definition

Colstrip 4 Return On Equity

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- Definition

Decrease in requested rate increase

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- Definition

Public Utilities, Overall Rate Of Return

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- Definition

Public Utilities Rate Base

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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 interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

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No definition available.

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- Definition

Percentage of public utility's requested debt to capital, including debt and equity.

+ References

No definition available.

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- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

+ References

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- Definition

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

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- Definition

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

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No definition available.

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- Definition

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

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No definition available.

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- Definition

Percentage of public utility's requested return on equity.

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Regulatory Matters (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
Regulatory Matters (Details) - USD ($) $ in Millions	Apr. 30, 2019	Mar. 31, 2019	Sep. 30, 2018
Montana Electric Rate Filing [Member]
Public Utilities, General Disclosures [Line Items]
Requested Rate Increase, Amount			$ 34.9
Requested Rate Increase, Percentage			6.60%
Requested Return on Equity, Percentage			10.65%
Overall Rate Of Return			7.42%
Colstrip 4 Return On Equity			10.00%
Colstrip 4 Rate Of Return			8.25%
Rate Base			$ 2,350.0
Requested Debt Capital Structure, Percentage			51.00%
Requested Equity Capital Structure, Percentage			49.00%
Requested Interim Rate Increase, Montana Electric Rate Filing. [Member]
Public Utilities, General Disclosures [Line Items]
Interim Rate Increase, Amount			$ 13.8
Approved Interim Rate Increase, Montana Electric Rate Filing. [Member]
Public Utilities, General Disclosures [Line Items]
Interim Rate Increase, Amount		$ 10.5
Scenario, Forecast [Member] \| Montana Electric Rate Filing [Member]
Public Utilities, General Disclosures [Line Items]
Requested Rate Increase, Amended, Amount	$ 30.7
Decrease in requested rate increase	$ 4.2