Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Cash Flows From Operating Activities
Net income	$ 44,809	$ 40,611
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	22,915	22,060
Deferred compensation	(7,501)	2,694
Realized and unrealized (gains) losses on long-term investments	2,487	(534)
Stock-based compensation	2,957	2,539
Deferred income taxes	(2,545)	2,481
Other non-cash items	1,031	(40)
Changes in assets and liabilities:
Receivables, net	(80,344)	(63,243)
Inventories	481	(7,476)
Other current assets	(3,915)	(861)
Accounts payable and accrued liabilities	(1,183)	(9,377)
Pension liabilities	(599)	(451)
Environmental and legal liabilities	56	(21)
Deferred revenues	421	(80)
Net Cash Used In Operating Activities	(20,930)	(11,698)
Cash Flows From Investing Activities
Expenditures for property, plant and equipment	(60,288)	(37,632)
Asset acquisition (Note 17)		(3,503)
Business acquisition, net of cash acquired (Note 17)		(184,000)
Other, net	3,156	1,379
Net Cash Used In Investing Activities	(57,132)	(223,756)
Cash Flows From Financing Activities
Revolving debt and bank overdrafts, net (Note 6)	98,636	49,668
Other debt borrowings (Note 6)	75,000
Dividends paid	(7,513)	(6,861)
Company stock repurchased	(9,935)	(989)
Stock option exercises	114	381
Other, net	(1,469)	(2,272)
Net Cash Provided By Financing Activities	154,833	39,927
Effect of Exchange Rate Changes on Cash	84	(3,719)
Net Increase (Decrease) in Cash and Cash Equivalents	76,855	(199,246)
Cash and Cash Equivalents at Beginning of Period	159,186	349,938
Cash and Cash Equivalents at End of Period	236,041	150,692
Supplemental Cash Flow Information
Cash payments of income taxes, net of refunds/payments	8,312	6,638
Cash payments of interest	$ 2,500	$ 2,242