Operating Segments and Geographic Information - Reconciliation of Total Reportable Segments' Revenues and EBITDA to Consolidated Revenues and Consolidated Income Before Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Revenues and Consolidated Revenues	$ 2,512,084	$ 2,606,485	$ 2,301,260
Depreciation expense	(51,400)	(46,700)	(43,900)
Amortization of intangibles	(40,375)	(37,860)	(30,630)
Severance, restructuring, and acquisition integration costs	(18,654)	(16,470)	(18,367)
Asset impairments	0	0	(140,461)
Gain on sale of assets	12,056	37,891	0
Consolidated operating income	317,518	363,334	263,676
Interest expense, net	(33,625)	(43,554)	(62,693)
Loss on debt extinguishment	0	(6,392)	(5,715)
Non-operating pension benefit	1,863	4,005	4,476
Gain on sale of note receivable	0	0	27,036
Consolidated income from continuing operations before taxes	285,756	317,393	226,780
Gain (loss) associated with sale of businesses	12,056	37,891	0
Proceeds from disposal of tangible assets	13,785	43,534	$ 30,234
Impairment, Long-Lived Asset, Held-for-Use, Statement of Income or Comprehensive Income [Extensible Enumeration]			Asset impairments
Proceeds from sale of real estate		42,200
Gain on sale of real estate		37,900
Reportable Segment
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Segment Revenues and Consolidated Revenues	2,512,084	2,606,485	$ 2,301,260
Total Segment EBITDA	436,435	438,596	367,193
Depreciation expense	(51,379)	(46,669)	(43,073)
Amortization of intangibles	(40,375)	(37,860)	(30,630)
Severance, restructuring, and acquisition integration costs	(25,152)	(16,685)	(23,867)
Amortization of software development intangible assets	(7,692)	(3,875)	(1,579)
Adjustments related to acquisitions and divestitures	(6,177)	(7,833)	5,035
Asset impairments	0	0	(9,283)
Gain on sale of assets	12,056	37,891	0
Lease guarantees	4,100	10,100
Inventory adjustment	1,500	2,200
Gain (loss) associated with sale of businesses	(600)
Collection of receivable previously written off		4,500
Increase (decrease) in deferred compensation earnout payments			(5,800)
Proceeds from disposal of tangible assets			600
Impairment of long lived asset held-for-use			3,600
Asset impairments			5,700
Proceeds from sale of real estate	13,800	42,200
Gain on sale of real estate	12,100	37,900
Reportable Segment | OTN Systems
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Adjustments related to acquisitions and divestitures			2,300
Reportable Segment | Grass Valley
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Recovery of accounts receivable previously written off			2,200
Eliminations
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Consolidated operating income	$ (198)	$ (231)	$ (120)