Pension and Other Postretirement Benefit Plans (Details) - USD ($)	6 Months Ended
Jun. 30, 2025	Dec. 31, 2024
Outside Director Pension Plan
Contribution to employee benefit plans		$ 100,000
Other Postretirement Benefit Plans
Contribution to employee benefit plans		$ 300,000
Contribution to other postretirement benefit plans	$ 20,000
Employee Pension Plan \| Savings Bank
Contribution to employee benefit plans	$ 0

Amount of contribution received by defined benefit plan from employer which increases plan assets.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration