Estimated Project Cost

No definition available.

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- Definition

Public utilities refund from current rates, percentage.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

+ Details

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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.

+ References

No definition available.

+ Details

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- Definition

Amount of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's interim rate increase (decrease) allowed while waiting final decision of regulatory agency.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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- Details

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- Details

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- Details

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- Details

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- Details

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North Dakota Public Service Commission (NDPSC) (Details 4) - NDPSC [Member] - USD ($) $ in Millions	Sep. 06, 2017	Jul. 26, 2017	Jul. 21, 2017	Jun. 30, 2017	Jun. 16, 2017	Nov. 21, 2016	Oct. 14, 2016	Mar. 09, 2016	Feb. 10, 2016	Jan. 05, 2016
Advance determination of prudence [Member]
Public Utilities, General Disclosures [Line Items]
Estimated project cost				$ 85.0
Natural gas rate proceeding [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount			$ 5.9
Public utilities, requested rate increase (decrease), percentage			5.40%
Public utilities, interim rate increase (decrease), amount	$ 4.6
Public utilities, interim rate increase (decrease), percentage	4.20%
Electric rate proceeding [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, requested rate increase (decrease), amount							$ 13.4
Public utilities, requested rate increase (decrease), percentage							6.60%
Public utilities, interim rate increase (decrease), amount						$ 11.7	$ 13.0
Public utilities, interim rate increase (decrease), percentage						5.80%	6.50%
Public utilities, approved rate increase (decrease), amount					$ 7.5
Public utilities, approved rate increase (decrease), percentage					3.70%
Public utilities refund from current rates, percentage		19.00%
Electric rider [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, approved return on equity, percentage					9.45%
Electric renewable cost rider [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, interim rate increase (decrease), amount										$ 15.1
Public utilities, approved return on equity, percentage					9.65%
Public utilities, requested return on equity, percentage										10.50%
Electric transmission adjustment [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, interim rate increase (decrease), amount									$ 6.8
Public utilities, requested rate increase (decrease), amended, percentage									10.50%
Electric generation rider [Member]
Public Utilities, General Disclosures [Line Items]
Public utilities, interim rate increase (decrease), amount								$ 9.7
Public utilities, approved return on equity, percentage					9.45%
Public utilities, requested return on equity, percentage								10.50%