Postretirement Benefits - Schedule of Defined Benefit Plan Amounts Recognized in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in benefit obligation:
Benefit obligation at beginning of year	$ 2,787	$ 2,987
Service cost	60	61	$ 53
Interest cost	53	87	105
Participant contribution	22	29
Actuarial (gains) / losses	13	(195)	310
Benefits paid	(176)	(182)
Benefit obligation at end of year	2,759	2,787	$ 2,987
Change in fair value of plan assets:
Employer contribution	154	153
Participant contribution	22	29
Benefits paid	(176)	(182)
Balance at end of year	0
Funded status at end of year	$ (2,759)	$ (2,787)