Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2019	Jun. 30, 2018
Cash Flows From Operating Activities
Net income	[1],[2]	$ 55,188	$ 65,397
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization		38,959	40,500
Deferred compensation		9,868	749
Realized and unrealized gains on long-term investments		(3,130)	(504)
Stock-based compensation		4,772	3,387
Deferred income taxes	[1]	223	3,034
Other non-cash items		2,262	830
Changes in assets and liabilities:
Receivables, net		(6,868)	(23,969)
Inventories	[1]	15,515	(16,738)
Other current assets		(3,981)	442
Accounts payable and accrued liabilities		(33,888)	(18,579)
Pension liabilities		(635)	(122)
Environmental and legal liabilities		630	(479)
Deferred revenues		(162)	(162)
Net Cash Provided By Operating Activities		78,753	53,786
Cash Flows From Investing Activities
Expenditures for property, plant and equipment		(45,084)	(43,741)
Business acquisition (Note 18)			(21,475)
Other, net		2,023	1,775
Net Cash Used In Investing Activities		(43,061)	(63,441)
Cash Flows From Financing Activities
Revolving debt and bank overdrafts, net		(6,272)	1,893
Other debt repayments		(37,143)	(5,714)
Dividends paid		(11,285)	(10,160)
Company stock repurchased		(6,181)	(12,000)
Stock option exercises		2,163	3,274
Other, net		(2,656)	(4,432)
Net Cash Used In Financing Activities		(61,374)	(27,139)
Effect of Exchange Rate Changes on Cash		754	(5,364)
Net Decrease in Cash and Cash Equivalents		(24,928)	(42,158)
Cash and Cash Equivalents at Beginning of Period		300,194	298,894
Cash and Cash Equivalents at End of Period		275,266	256,736
Supplemental Cash Flow Information
Cash payments of income taxes, net of refunds/payments		11,895	19,739
Cash payments of interest		$ 7,164	$ 6,444

[1] The 2018 amounts for the noted line items have been retrospectively changed from the amounts originally reported as a result of the Company’s first quarter 2019 change in method of accounting for U.S. inventory valuation from LIFO to FIFO.

[2] The 2018 amounts for the noted line items have been retrospectively changed from the amounts originally reported as a result of the Company’s first quarter 2019 change in method of accounting for U.S. inventory valuation from the last in, first out (LIFO) basis to the first in, first out (FIFO) basis.