Reportable Segments - Reconciliation of Total Reportable Segments' Revenues and EBITDA to Consolidated Revenues and Consolidated Income Before Taxes (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jul. 03, 2022	Jul. 04, 2021	Apr. 04, 2021	Jul. 03, 2022	Jul. 04, 2021
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Revenues	$ 666,551	$ 575,857		$ 1,276,922	$ 1,084,540
Depreciation expense	(11,400)	(10,700)		(22,600)	(21,400)
Amortization of intangibles	(9,177)	(7,172)		(17,994)	(15,165)
Severance, restructuring, and acquisition integration costs	(5,122)	(648)		(9,997)	(2,416)
Asset impairments	0	0		0	(6,995)
Operating income	81,936	68,349		155,457	119,297
Interest expense, net	(11,276)	(14,870)		(25,687)	(30,381)
Loss on debt extinguishment	0	0		(6,392)	0
Total non-operating pension benefit	1,070	1,445		2,270	2,129
Consolidated income from continuing operations before taxes	71,730	54,924		125,648	91,045
Reportable Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Revenues	666,551	576,706		1,276,922	1,085,389
Adjustments related to acquisitions	0	(849)		0	(849)
Total Segment EBITDA	109,947	91,465		208,296	167,367
Depreciation expense	(11,370)	(10,658)		(22,596)	(21,385)
Amortization of intangibles	(9,177)	(7,172)		(17,994)	(15,165)
Amortization of software development intangible assets	(981)	(322)		(1,988)	(731)
Severance, restructuring, and acquisition integration costs	(5,857)	(3,040)		(9,580)	(8,211)
Purchase accounting effects related to acquisitions	(576)	(1,912)		(576)	4,462
Asset impairments	0	0		0	(6,995)
Inventory adjustment	1,100			1,100
Collection of receivables, previously written off	500	100		500	1,400
Business combination, increase (decrease) in earn-out liability					5,800
Impairment of assets held-for-use			$ 3,600
Impairment of assets to be held for sale			$ 3,400
Reportable Segment | OTN Systems N.V.
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Inventory adjustment		1,200			2,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Revenue		800
Intersegment Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Eliminations	$ (50)	$ (12)		$ (105)	$ (45)