Postretirement Benefit Plans - Amounts Recognized in Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Defined Benefit Postretirement Health And Life Coverage
Defined Benefit Plan Disclosure [Line Items]
Net prior service cost, pretax	$ 0	$ 10
Unrecognized actuarial gain (loss)	38	18
Director's Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Net prior service cost, pretax	0	0
Unrecognized actuarial gain (loss)	(214)	(248)
Scottdale Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Unrecognized actuarial gain (loss)	581	1,030
Riverview Defined Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Unrecognized actuarial gain (loss)	$ 76	$ (824)

Amount, before tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482790/220-10-45-14A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (j)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480506/715-20-50-1

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- Definition

Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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- Definition

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+ References

No definition available.

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