Proposed Depreciation Rate Increase (Decrease) As Percentage Of Revenue

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Percentage of public utility's approved return on equity.

+ References

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- Definition

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

+ References

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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.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

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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.

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Regulatory matters - Schedule of Regulatory Proceedings (Details) - USD ($) $ in Millions	Dec. 01, 2026	Sep. 01, 2026	Jun. 30, 2026	Jun. 01, 2026	May 29, 2026	Apr. 01, 2026	Mar. 01, 2026	Nov. 25, 2025	Oct. 31, 2025	Sep. 30, 2025	Jun. 01, 2025	Mar. 05, 2025	Feb. 24, 2025
General Rate Cases Pending \| Pipeline
Regulatory Assets
Annual Revenue Increase (%), pending					13.50%
Annual Revenue Increase (in millions), pending					$ 31.0
ROE, pending					14.59%
General Rate Cases Pending \| Pipeline \| Forecast
Regulatory Assets
Proposed depreciation rate increase (decrease) as percentage of revenue	30.00%
Montana \| General Rate Cases Pending \| Electric
Regulatory Assets
Annual Revenue Increase (%), pending										15.00%
Annual Revenue Increase (in millions), pending										$ 10.0
ROE, pending										9.65%
Public utilities, interim rate increase (decrease), amount						$ 10.4
Interim rate increase (%) pending						16.20%
Oregon \| General Rate Cases Pending \| Natural Gas Distribution
Regulatory Assets
Annual Revenue Increase (%), pending								11.80%
Annual Revenue Increase (in millions), pending								$ 12.2
ROE, pending								9.50%
Washington \| General Rate Cases Pending \| Natural Gas Distribution
Regulatory Assets
ROE, pending					10.50%
Washington \| General Rate Cases Pending \| Natural Gas Distribution \| Year One
Regulatory Assets
Annual Revenue Increase (%), approved					4.90%
Annual Revenue Increase (in millions), approved					$ 25.1
Washington \| General Rate Cases Pending \| Natural Gas Distribution \| Year Two
Regulatory Assets
Annual Revenue Increase (%), approved					3.40%
Annual Revenue Increase (in millions), approved					$ 18.1
Washington \| General Rate Cases Finalized \| Natural Gas Distribution
Regulatory Assets
Annual Revenue Increase (%), approved							2.60%					7.90%
Annual Revenue Increase (in millions), approved				$ (2.1)			$ 10.8				$ (3.7)	$ 29.8
ROE, approved													9.50%
North Dakota \| General Rate Cases Pending \| Electric
Regulatory Assets
Annual Revenue Increase (%), pending			14.50%
Annual Revenue Increase (in millions), pending			$ 34.5
ROE, pending			10.80%
North Dakota \| General Rate Cases Pending \| Electric \| Forecast
Regulatory Assets
Public utilities, interim rate increase (decrease), amount		$ 26.3
Interim rate increase (%) pending		11.00%
Wyoming \| General Rate Cases Finalized \| Electric
Regulatory Assets
Annual Revenue Increase (%), approved						18.60%
Annual Revenue Increase (in millions), approved						$ 5.8
ROE, approved						9.70%
South Dakota \| Electric
Regulatory Assets
Annual Revenue Increase (in millions), pending									$ 1.1