Consolidated Statements of Cash Flows - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Cash Flows From Operating Activities
Net income	$ 40,204,000	$ 147,153,000	$ 137,895,000
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	105,338,000	94,650,000	90,876,000
Deferred compensation	4,371,000	(9,393,000)	6,895,000
Realized and unrealized (gains) losses on long-term investments	(4,314,000)	8,188,000	(2,289,000)
Stock-based compensation	5,741,000	13,851,000	11,716,000
Deferred income taxes	18,303,000	(27,452,000)	(33,605,000)
Goodwill and other intangibles impairment (Note 4)	2,038,000	978,000
Other non-cash items	5,123,000	1,752,000	2,158,000
Changes in assets and liabilities, excluding effects of acquisitions:
Receivables, net	32,007,000	(26,153,000)	(104,231,000)
Inventories	144,846,000	(99,394,000)	(79,258,000)
Other current assets	(4,528,000)	(4,354,000)	(1,434,000)
Accounts payable and accrued liabilities	(158,924,000)	54,173,000	44,414,000
Pension liabilities	(1,204,000)	(1,821,000)	(1,729,000)
Environmental and legal liabilities	(11,985,000)	9,547,000	450,000
Deferred revenues	(2,140,000)	(962,000)	277,000
Net Cash Provided By Operating Activities	174,876,000	160,763,000	72,135,000
Cash Flows From Investing Activities
Expenditures for property, plant and equipment	(260,335,000)	(301,553,000)	(194,482,000)
Proceeds from asset disposition			4,149,000
Asset acquisition (Note 20)			(3,503,000)
Business acquisitions, net of cash acquired (Note 20)		(9,693,000)	(184,473,000)
Other, net	1,669,000	3,156,000	1,480,000
Net Cash Used In Investing Activities	(258,666,000)	(308,090,000)	(376,829,000)
Cash Flows From Financing Activities
Revolving debt and bank overdrafts, net (Note 6)	104,717,000	186,551,000	2,861,000
Other debt borrowings (Note 6)		75,000,000	200,000,000
Other debt repayments (Note 6)	(37,858,000)	(37,857,000)	(37,858,000)
Dividends paid	(32,868,000)	(30,573,000)	(28,083,000)
Company stock repurchased		(24,949,000)	(16,969,000)
Stock option exercises	2,795,000	782,000	1,369,000
Other, net	(3,502,000)	(2,745,000)	(3,987,000)
Net Cash Provided By Financing Activities	33,284,000	166,209,000	117,333,000
Effect of Exchange Rate Changes on Cash	6,579,000	(4,318,000)	(3,391,000)
Net Increase (Decrease) in Cash and Cash Equivalents	(43,927,000)	14,564,000	(190,752,000)
Cash and Cash Equivalents at Beginning of Year	173,750,000	159,186,000	349,938,000
Cash and Cash Equivalents at End of Year	129,823,000	173,750,000	159,186,000
Supplemental Cash Flow Information
Cash payments of income taxes, net of refunds/payments	29,558,000	41,617,000	92,867,000
Cash payments of interest	$ 27,951,000	$ 16,526,000	$ 9,542,000