Condensed Consolidated Income Statements - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 05, 2020	Mar. 31, 2019
Revenue from Contract with Customer, Excluding Assessed Tax	$ 652,396	$ 648,737
Cost of Goods and Services Sold	344,373	340,931
Selling, general and administrative expenses	208,569	198,857
Research and development expenses	48,914	47,980
Restructuring and other costs, net	5,858	7,639
Operating income from continuing operations	44,682	53,330
Interest and other expense, net	9,993	16,565
Interest And Other Expense Net	9,993	(16,565)
Income from continuing operations before income taxes	34,689	36,765
Provision for income taxes	974	1,312
Income from continuing operations	33,715	35,453
Loss on disposition of discontinued operations before income taxes	0	0
Provision for income taxes on discontinued operations and dispositions	50	41
Loss from discontinued operations and dispositions	(50)	(41)
Net income	$ 33,665	$ 35,412
Basic earnings (loss) per share:
Income (loss) from continuing operations (per share)	$ 0.30	$ 0.32
Gain (loss) on discontinued operations and dispositions (per share)	0.00	0.00
Net income (per share)	0.30	0.32
Diluted earnings (loss) per share:
Income (loss) from continuing operations (per share)	0.30	0.32
Gain (loss) on discontinued operations and dispositions (per share)	0.00	0.00
Net income (per share)	$ 0.30	$ 0.32
Weighted average shares of common stock outstanding:
Basic (in shares)	111,121	110,543
Diluted (in shares)	111,644	111,293
Cash dividends per common share	$ 0.07	$ 0.07
Product [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 425,529	$ 438,722
Cost of Goods and Services Sold	206,190	206,276
Service [Member]
Revenue from Contract with Customer, Excluding Assessed Tax	226,867	210,015
Cost of Goods and Services Sold	$ 138,183	$ 134,655