Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net earnings	$ 123,783	$ 164,790	$ 346,537
Adjustments to reconcile net earnings (loss) to net cash provided by operating activities:
Depreciation and amortization	166,230	164,461	161,863
(Gain) loss on disposal of property and equipment	157	(157)	(2,216)
Accretion of interest on convertible debt instruments	13,161	14,146	10,769
Inventory write-offs for obsolescence	22,730	26,494	23,872
Pensions and other postretirement benefits, net of contributions	2,864	(552)	(1,549)
Loss on early extinguishment of debt	8,073	2,030	26,583
Deferred income taxes	(12,141)	(23,009)	(55,206)
Other	3,304	13,341	21,194
Change in U.S. transition tax liability	(14,757)	(14,757)	(14,757)
Change in repatriation tax liability	(16,258)	(38,814)	(156,767)
Net change in operating assets and liabilities, net of effects of businesses acquired	17,792	(11,529)	(101,817)
Net cash provided by operating activities	314,938	296,444	258,506
Investing activities
Capital expenditures	(123,599)	(156,641)	(229,899)
Proceeds from sale of property and equipment	403	577	55,561
Purchase of businesses, net of cash acquired	(25,852)	(11,862)	(14,880)
Purchase of short-term investments	(293,087)	(111,631)	(175,403)
Maturity of short-term investments	250,580	81,012	636,108
Other investing activities	(529)	3,587	(2,058)
Net cash provided by (used in) investing activities	(192,084)	(194,958)	269,429
Financing activities
Proceeds from long-term borrowings	0	0	600,000
Issuance costs	0	(5,394)	(15,621)
Repurchase of convertible debentures	(151,683)	(27,863)	(960,995)
Net proceeds (payments) on revolving credit lines	0	0	(150,000)
Net changes in short-term borrowings	(114)	(16)	15
Distributions to noncontrolling interests	(600)	(600)	(525)
Cash withholding taxes paid when shares withheld for vested equity awards	(2,016)	(2,708)	(2,297)
Net cash used in financing activities	(209,382)	(90,025)	(575,932)
Effect of exchange rate changes on cash and cash equivalents	12,269	(3,360)	(14,003)
Net increase (decrease) in cash and cash equivalents	(74,259)	8,101	(62,000)
Cash and cash equivalents at beginning of year	694,133	686,032	748,032
Cash and cash equivalents at end of year	619,874	694,133	686,032
Common Stock [Member]
Operating activities
Net earnings	0	0	0
Financing activities
Dividends paid	(50,372)	(48,968)	(42,608)
Class B Convertible Common Stock [Member]
Operating activities
Net earnings	0	0	0
Financing activities
Dividends paid	$ (4,597)	$ (4,476)	$ (3,901)