The increase (decrease) during the reporting period in unrecovered fuel costs for a regulated utility company.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

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- Definition

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

+ References

No definition available.

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- Definition

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

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No definition available.

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- Definition

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

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- Definition

Percentage of public utility's approved return on equity.

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- Definition

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

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- Definition

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

+ References

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Percentage of public utility's requested return on equity.

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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

Expenses associated with the program excluded from the revenue requirement as per order and adjusted increase amount will result in reasonable rates

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- Definition

Increase Decrease Transfer Cost Amount

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- Definition

Public utilities approved increase amount of annual revenue to recover eligible capital investments

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- Definition

Weighted Average Cost Of Capital

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Regulatory Matters - Additional Information (Detail) - USD ($) $ in Millions	Jul. 16, 2024	Jun. 28, 2024	May 01, 2024	Nov. 27, 2023	Nov. 01, 2023	Sep. 20, 2023	Aug. 17, 2023	Jul. 26, 2023	May 31, 2023	Jul. 28, 2022	Jul. 20, 2022	Jun. 08, 2022	May 12, 2022	May 03, 2022
Regulatory Asset [Line Items]
Requested annual increase in rates			$ 2.4
Northern Utilities Inc
Regulatory Asset [Line Items]
Percentage of approved return on equity													9.20%
Percentage of approved return on equity, reflecting on equity													52.00%
Percentage of approved return on equity, reflecting on debt													48.00%
Approved annual increase in rates						$ 7.6								$ 6.3
Return on equity						9.35%
Equity ratio						52.01%
Weighted Average Cost Of Capital						7.22%
Public utilities approved increase amount of annual revenue to recover eligible capital investments									$ 1.2	$ 1.3
Northern Utilities Inc \| Settlement Agreement [Member]
Regulatory Asset [Line Items]
Approved annual increase in rates											$ 6.1
Northern Utilities Inc \| Arrearage Management Program [Member]
Regulatory Asset [Line Items]
Expenses associated with the program excluded from the revenue requirement as per order and adjusted increase amount will result in reasonable rates													$ 5.9
Northern Utilities Inc \| New Hampshire
Regulatory Asset [Line Items]
Percentage of approved return on equity											9.30%
Percentage of approved return on equity, reflecting on equity											52.00%
Percentage of approved return on equity, reflecting on debt											48.00%
Requested annual increase in rates												$ 1.6
Fitchburg Gas and Electric Light Company
Regulatory Asset [Line Items]
Increase (decrease) in annual revenue				$ 3.5	$ 3.6			$ 3.1
Percentage of approved return on equity		9.40%
Percentage of approved return on equity, reflecting on equity		52.00%
Percentage of approved return on equity, reflecting on debt		48.00%
Increase in cost		$ 2.2
Fitchburg Gas and Electric Light Company \| Subsequent Event [Member]
Regulatory Asset [Line Items]
Increase in cost	$ 0.8
Fitchburg Gas and Electric Light Company \| July 1, 2024 [Member]
Regulatory Asset [Line Items]
Approved annual increase in rates		$ 4.7					$ 6.8