Consolidated Statements of Earnings (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 25, 2020	Sep. 27, 2019	Sep. 25, 2020	Sep. 27, 2019
Income Statement [Abstract]
Revenues	$ 439,316	$ 400,555	$ 1,179,775	$ 1,233,753
Cost of Goods and Services Sold	210,363	193,176	569,662	583,378
Gross Profit	228,953	207,379	610,113	650,375
Product development	17,715	16,723	52,744	50,616
Selling, marketing and distribution	54,009	55,538	160,228	176,796
General and administrative	31,957	31,719	102,322	102,676
Impairment	267	0	35,229	0
Operating Earnings	125,005	103,399	259,590	320,287
Interest expense	2,964	3,618	8,708	10,584
Other expense (income), net	1,025	2,972	5,738	4,360
Earnings Before Income Taxes	121,016	96,809	245,144	305,343
Income taxes	6,901	12,677	29,379	46,325
Net Earnings	$ 114,115	$ 84,132	$ 215,765	$ 259,018
Basic earnings per share	$ 0.68	$ 0.50	$ 1.29	$ 1.56
Diluted earnings per share	$ 0.66	$ 0.49	$ 1.26	$ 1.51