Consolidated Condensed Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Apr. 04, 2020	Mar. 30, 2019
Operating activities
Net earnings	$ 27,384	$ 75,641
Adjustments to reconcile net earnings to net cash provided by operating activities:
Depreciation and amortization	41,520	40,428
(Gain) loss on disposal of property and equipment	(45)	(173)
Accretion of interest on convertible debt instruments	3,637	3,490
Inventory write-offs for obsolescence	5,643	6,967
Deferred income taxes	(3,517)	(2,614)
Loss on extinguishment of debt	2,920	1,307
Other	3,524	(1,744)
Net change in operating assets and liabilities, net of effects of businesses acquired	(46,588)	(43,784)
Net cash provided by operating activities	34,478	79,518
Investing activities
Capital expenditures	(24,328)	(36,367)
Proceeds from sale of property and equipment	53	395
Purchase of businesses, net of cash received	0	(11,862)
Purchase of short-term investments	(35,463)	(1,920)
Maturity of short-term investments	0	71,455
Other investing activities	(1,507)	2,893
Net cash provided by (used in) investing activities	(61,245)	24,594
Financing activities
Repurchase of convertible debentures	(19,849)	(22,695)
Net proceeds (payments) on revolving credit lines	54,000	0
Net changes in short-term borrowings	85	0
Cash withholding taxes paid when shares withheld for vested equity awards	(1,991)	(2,659)
Net cash provided by (used in) financing activities	18,504	(37,631)
Effect of exchange rate changes on cash and cash equivalents	(5,167)	(3,087)
Net increase (decrease) in cash and cash equivalents	(13,430)	63,394
Cash and cash equivalents at beginning of period	694,133	686,032
Cash and cash equivalents at end of period	680,703	749,426
Common Stock [Member]
Operating activities
Net earnings	0	0
Financing activities
Dividends paid to common stockholders	(12,592)	(11,249)
Class B Convertible Common Stock [Member]
Operating activities
Net earnings	0	0
Financing activities
Dividends paid to common stockholders	$ (1,149)	$ (1,028)