Pension Plan (Details) - Change in unrecognized pension costs recorded in other comprehensive loss - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Pension Plan (Details) - Change in unrecognized pension costs recorded in other comprehensive loss [Line Items]
Balance at beginning of year	$ 9,051,000	$ 8,296,000
Net actuarial (gain) loss	(428,000)	1,043,000
Recognized loss	(622,000)	(288,000)
Balance at end of year	$ 8,001,000	$ 9,051,000