REGULATORY ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	$ 61,487		$ 49,504
Regulatory assets, noncurrent	252,048		256,225
Regulatory Assets	313,535		305,729
Regulatory Liability, Current	(21,638)		(57,277)
Regulatory Liability, Noncurrent	(441,041)		(451,620)
Regulatory Liabilities	(462,679)		(508,897)
Net Regulatory Assets (Liabilities), Current	39,849		(7,773)
Net regulatory assets and liabilities, noncurrent	(188,993)		(195,395)
Net Regulatory Assets (Liabilities)	(149,144)		(203,168)
Amortization of Rate Deferral	0	$ 6,000
Income tax rate changes [Member] [Domain]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current	0		0
Regulatory Liability, Noncurrent	(432,690)		(444,986)
Regulatory Liabilities	(432,690)		(444,986)
Over-recovered purchased-gas costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current	(18,378)		(56,876)
Regulatory Liability, Noncurrent	0		0
Regulatory Liabilities	(18,378)		(56,876)
Ad valorem tax [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current	(1,553)		(165)
Regulatory Liability, Noncurrent	0		0
Regulatory Liabilities	(1,553)		(165)
Other regulatory liabilities
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory Liability, Current	(1,707)		(236)
Regulatory Liability, Noncurrent	(8,351)		(6,634)
Regulatory Liabilities	(10,058)		(6,870)
Under-recovered purchased-gas costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	2,261		10,692
Regulatory assets, noncurrent	0		0
Regulatory Assets	2,261		10,692
Pension and postretirement benefit costs, net [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	10,187		10,929
Regulatory assets, noncurrent	217,257		221,809
Regulatory Assets	227,444		232,738
Reacquired debt costs [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	723		723
Regulatory assets, noncurrent	1,085		1,266
Regulatory Assets	1,808		1,989
MGP Costs [Member] [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	1,000		1,000
Regulatory assets, noncurrent	29,592		29,105
Regulatory Assets	30,592		30,105
Weather normalization [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	25,165		19,175
Regulatory assets, noncurrent	0		0
Regulatory Assets	25,165		19,175
Customer credit deferrals
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	14,779		2,953
Regulatory assets, noncurrent	1,081		1,091
Regulatory Assets	15,860		4,044
Other regulatory assets, net [Member]
SCHEDULE OF REGULATED ASSETS AND LIABILITIES [Line Items]
Regulatory assets, current	7,372		4,032
Regulatory assets, noncurrent	3,033		2,954
Regulatory Assets	$ 10,405		$ 6,986

The net amount of all current regulatory assets less all current regulatory liabilities as of the end of the period.

No definition available.

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- Definition

The net amount of noncurrent regulatory assets less all noncurrent regulatory liabilities as of the end of the period.

+ References

No definition available.

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[Line Items] for Tabular disclosure of assets and liabilities that result from rate actions of a regulator. Regulatory assets are created when regulatory agencies permit public utilities to defer certain costs included in rate-setting to the balance sheet. Rate actions of a regulator can impose a liability on a regulated enterprise resulting in a regulatory liability.

+ References

No definition available.

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The periodic expense to reduce the value of the rate deferral asset that is created when utilities under bill customers during periods of rate increases by deferring rate increases. These customers eventually pay higher rates to repay the utility for the rate deferral.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
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The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost.

+ References

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Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477571/980-405-25-1

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The amount for the individual regulatory current liability as itemized in a table of regulatory current liabilities as of the end of the period.

+ References

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The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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