Accrued Expenses Components of Accrued Expenses (Details) - USD ($)	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Payables and Accruals [Abstract]
Salaries and wages	$ 27,473,000	$ 23,289,000
Taxes other than income taxes, primarily Value Added Taxes	21,703,000	23,197,000
Warranty	12,796,000	16,353,000
Professional	6,695,000	5,888,000
Rebates	6,754,000	7,966,000
Advance payment on sale of land & buildings	3,436,000	0
Interest	3,284,000	3,992,000
Freight	2,887,000	3,363,000
Deferred revenue	2,887,000	2,416,000
Product liability, current portion	2,806,000	2,728,000
Severance	1,171,000	1,657,000
Insurance	618,000	738,000
Rent	514,000	483,000
Supplemental Executive Retirement Program liability	391,000	391,000
Derivative liabilities (foreign currency forward exchange contracts)	180,000	219,000
Other items, principally trade accruals	7,529,000	7,187,000
Accrued expenses	$ 101,124,000	$ 99,867,000
Net Book Value of Assets Sold			$ 2,900,000