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Employee Postretirement Benefits - Composition of Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Retirement Benefits [Abstract]
Net Periodic Benefit Cost (Income)	$ (1,566)	$ 1,480	$ (3,132)	$ 2,959
Net Amount Amortized (Deferred) Due to the Effect of Regulation	240	(204)	490	324
Net Periodic Benefit Cost (Income) Recognized	$ (1,326)	$ 1,276	$ (2,642)	$ 3,283

X

- Definition

Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Deferred

+ References

No definition available.

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X

- Definition

Defined Benefit Plan, Net Periodic Benefit Cost (Credit), Net of Deferrals

+ References

No definition available.

+ Details

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- References

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X

- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480482/715-20-55-17

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
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-Name Accounting Standards Codification
-Section 55
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-URI https://asc.fasb.org//1943274/2147480482/715-20-55-18

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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