Employee Benefit Plans - Schedule of beginning and ending balances of accumulated postretirement benefit obligations (Details) - Other Postretirement Benefit Plans - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Employee Benefit Plans
Accumulated postretirement benefit obligations at the beginning of the year	$ 5,865,000	$ 2,529,000
Service Cost		46,000
Interest Cost	157,000	65,000
Actuarial (gain)/loss	(1,838,000)	3,308,000
Benefits paid	(122,000)	(83,000)
Accumulated postretirement benefit obligations at the end of the year	$ 4,062,000	$ 5,865,000