INCOME TAXES - Tax Effects and Tax Cuts and Jobs Act (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Schedule of components of income before income taxes
Domestic	$ 10,642	$ 8,478	$ 17,188
Foreign	12,471	10,298	6,653
Income before income taxes	23,113	18,776	23,841
Current provision
Domestic	1,866	2,167	4,313
Foreign	3,288	3,485	2,618
Total current provision	5,154	5,652	6,931
Deferred (benefit) provision
Domestic	649	288	199
Foreign	(6,784)	(807)	(311)
Total deferred (benefit) provision	(6,135)	(519)	(112)
Income tax (benefit) provision	$ (981)	$ 5,133	$ 6,819
Differences in the (benefit) provision for income taxes from the amount determined by applying the federal statutory rate
Tax provision, computed at statutory rate (as a percent)	21.00%	21.00%	21.00%
State tax, net of federal impact (as a percent)	2.20%	4.20%	4.50%
Change in valuation allowance (as a percent)	7.20%	0.00%	0.30%
Effect of foreign tax rate differences (as a percent)	3.90%	4.30%	1.50%
Permanent items, other (as a percent)	0.20%	(0.20%)	1.40%
Section 162(m) compensation	3.00%	2.20%	1.10%
R&D tax credits (as a percent)	(2.80%)	(3.60%)	(2.50%)
Effect of Tax Cuts and Jobs Act (as a percent)	1.20%	(1.30%)	(0.40%)
Subpart F income (as a percent)	(1.00%)	1.30%	0.00%
Tax examinations (as a percent)	0.00%	0.00%	1.80%
Investment tax credits (as a percent)	(5.60%)	(0.00%)	(0.00%)
Net operating loss carryforwards (as a percent)	(37.20%)	(0.00%)	(0.00%)
Unrecognized tax benefits (as a percent)	4.90%	0.00%	0.00%
Other (as a percent)	(1.20%)	(0.60%)	(0.10%)
Income tax (benefit) provision (as a percent)	(4.20%)	27.30%	28.60%
Noncurrent deferred tax assets:
Employee benefit plans	$ 2,085	$ 2,500
Net operating loss and tax credit carryforwards	9,802	2,217
Accrued expenses and reserves	915	969
Other	218	697
Total noncurrent deferred tax assets	13,020	6,383
Valuation allowance	(2,896)	(1,176)
Net noncurrent deferred tax assets:	10,124	5,207
Net noncurrent deferred tax liabilities:
Property and equipment	3,238	3,448
Goodwill and intangibles	6,484	5,629
Other	121	459
Total noncurrent deferred tax liabilities	9,843	9,536
Noncurrent deferred income tax assets	5,321	330
Noncurrent deferred income tax liabilities	(5,040)	(4,659)
Net deferred tax asset	281
Net deferred tax asset/(deferred tax liability)		$ (4,329)
Foreign Tax Credit [Member]
Net noncurrent deferred tax liabilities:
Tax Credit Carryforward, Amount	92
Domestic Tax Authority [Member]
Net noncurrent deferred tax liabilities:
Operating Loss Carryforwards	4,812
Domestic Tax Authority [Member] | Foreign Tax Credit [Member]
Net noncurrent deferred tax liabilities:
Tax Credit Carryforward, Amount	1,003
Foreign
Net noncurrent deferred tax liabilities:
Operating Loss Carryforwards	1,678
Operating Loss Carryforwards, Unlimited Carryforward	22,886
Foreign | R&D Tax Credits
Net noncurrent deferred tax liabilities:
Tax Credit Carryforward, Amount	$ 513