Pension and Other Postretirement Benefit Plans - Projected Benefit Obligation and Fair Value of Plan Asset (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Projected Benefit Obligation:
Projected benefit obligation at beginning of year	$ 63,129,000	$ 74,683,000
Interest cost	581,000	323,000	$ 679,000
Benefits paid and administrative expenses	(1,398,000)	(1,426,000)
Actuarial (gain) loss, net	(18,361,000)	(5,281,000)
Unrealized (gain) loss on foreign exchange	(3,892,000)	(5,170,000)
Projected benefit obligation at end of year	40,059,000	63,129,000	74,683,000
Fair Value of Plan Assets:
Fair value of plan assets at beginning of year	59,039,000	70,319,000
Increase in plan asset value	(17,213,000)	(5,268,000)
Employer contributions	603,000	261,000		$ 0
Unrealized gain (loss) on foreign exchange	(3,655,000)	(4,847,000)
Fair value of plan assets at end of year	37,376,000	59,039,000	$ 70,319,000
Under-funded status of the plan at end of the year	(2,683,000)	(4,090,000)
Accumulated Benefit Obligation	$ 37,391,000	$ 63,129,000