BUSINESS AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Warranty, Accrued Liabilities, and Basic and Diluted Income per Share (Details) - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Changes in the reserve for product warranty claims
Warranty reserve at beginning of the year	$ 1,571	$ 1,075	$ 971
Warranty reserves acquired	15	465
Provision	543	34	210
Warranty expenditures	(204)	(97)	(101)
Effect of foreign currency translation	(56)	94	(5)
Warranty reserve at end of year	1,869	1,571	1,075
ACCRUED LIABILITIES
Compensation and fringe benefits	14,666	11,184
Accrued business acquisition consideration (Note 2)	12,388
Right of use liabilities	$ 4,532	$ 4,666
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Accrued liabilities	Accrued liabilities
Warranty reserve	$ 1,869	$ 1,571	$ 1,075
Income taxes payable	970	1,459
Other accrued expenses	7,231	5,982
Accrued liabilities	$ 41,656	$ 24,862
Basic and Diluted Income per Share
Basic weighted average shares outstanding	14,413	14,243	14,097
Dilutive effect of potential common shares	104	90	95
Diluted weighted average shares outstanding	14,517	14,333	14,192
Minimum
Warranty
Warranty period	3 months
Maximum
Warranty
Warranty period	2 years