Accrued Liabilities (Details) - Accrued liabilities - USD ($)	Dec. 31, 2021	Dec. 31, 2020
Accrued Liabilities (Details) - Accrued liabilities [Line Items]
Taxes payable	$ 1,195,000	$ 1,149,000
Interest payable	1,173,000	933,000
Warranty reserve	380,000	438,000
Deferred revenues	284,000	271,000
Compensation and employee benefits	225,000	90,000
Audit fees	134,000	134,000
Current portion of pension liability (see Note 15 – Pension Plan)	128,000	1,008,000
Other	768,000	532,000
Accrued Liabilities, Total	$ 4,287,000	$ 4,555,000