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Employee Postretirement Benefits - Composition of Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Retirement Benefits [Abstract]
Net Periodic Benefit Cost	$ 1,480	$ 2,843	$ 2,959	$ 5,684
Net Amount Amortized (Deferred) Due to the Effect of Regulation	(204)	123	324	7
Net Periodic Benefit Cost Recognized	$ 1,276	$ 2,966	$ 3,283	$ 5,691

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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
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-Publisher FASB
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