Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
OPERATING ACTIVITIES
Net income	$ 27,086	$ 28,075
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation	15,864	15,597
Amortization	1,503	2,165
Change in deferred taxes and other liabilities	(887)	1,792
Impairment of property, plant, equipment, and inventory	100	2,868
Non-cash interest expense	280	282
Compensation and benefits paid or payable in Class A Common Stock	378	745
Provision/(recovery) for credit losses from uncollected receivables and contract assets	309	1,858
Foreign currency remeasurement (gain)/loss on intercompany loans	(1,732)	(2,385)
Fair value adjustment on foreign currency options	58	(977)
Changes in operating assets and liabilities that provided/(used) cash:
Accounts receivable	(13,702)	(15,674)
Contract assets	(4,403)	272
Inventories	(12,360)	(7,549)
Prepaid expenses and other current assets	(2,191)	(1,976)
Income taxes prepaid and receivable	(693)	1,829
Accounts payable	5,214	(375)
Accrued liabilities	(23,137)	(19,350)
Income taxes payable	(10,996)	(10,890)
Noncurrent receivables	867	614
Other noncurrent liabilities	7	(1,914)
Other, net	2,042	(398)
Net cash used in operating activities	(16,393)	(5,391)
INVESTING ACTIVITIES
Purchases of property, plant and equipment	(16,275)	(15,719)
Purchased software	0	(35)
Net cash used in investing activities	(16,275)	(15,754)
FINANCING ACTIVITIES
Proceeds from borrowings	58,000	77,000
Principal payments on debt	(6,000)	0
Principal payments on finance lease liabilities	0	(390)
Purchase of Treasury shares	0	(42,230)
Taxes paid in lieu of share issuance	(3,136)	(770)
Proceeds from options exercised	0	7
Dividends paid	(7,778)	(6,742)
Net cash provided by financing activities	41,086	26,875
Effect of exchange rate changes on cash and cash equivalents	4,064	(351)
Increase in cash and cash equivalents	12,482	5,379
Cash and cash equivalents at beginning of period	291,776	302,036
Cash and cash equivalents at end of period	$ 304,258	$ 307,415