Postretirement Benefit Plans - Amounts Recognized in Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Defined Benefit Postretirement Health And Life Coverage
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	$ (18)	$ 82
Net prior service cost, pretax	10	(15)
Director's Retirement Plan
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	248	189
Net prior service cost, pretax	0	0
Scottdale Defined Benefit Pension Plan
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	(1,030)	(602)
Riverview Defined Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain), pretax	$ 824	$ (176)

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://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (j)
-URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580

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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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