Discontinued Operations - Additional Information (Details) - USD ($)		3 Months Ended	12 Months Ended
	Jul. 02, 2020	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Goodwill impairment loss			$ 0	$ 0	$ 0
Proceeds from disposal of business, net of cash sold			54,821,000	0	40,171,000
Depreciation and amortization			0.0	23,700,000	35,100,000
Capital expenditure			16,700,000	29,400,000	22,600,000
Share-based compensation expense			(900,000)	900,000	1,400,000
Accumulated other comprehensive income (loss), net of tax				42,300,000
Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of the disposal group				179,300,000
Translation exchange rates				180,400,000
Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Loss on sale, discontinued operations	$ 9,900,000
Tax effect of discontinued operation	7,500,000
Grass Valley
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of the disposal group			113,000,000.0	521,400,000
Equity interest in divested business	$ 3,000,000.0
Equity interest in divested business, percentage	9.00%
Proceeds from sale of equity interest under cost method		$ 2,700,000
Accrued interest		7,800,000
Revenues		$ 2,000,000.0
Grass Valley | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of the disposal group			113,007,000	521,441,000	0
Goodwill impairment loss				326,100,000
Impairment of the disposal group			179,300,000
Translation exchange rates			180,400,000
Revenues			109,195,000	360,496,000	$ 419,666,000
Grass Valley | Discontinued Operations, Disposed of by Sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of businesses	$ 120,000,000.0
Proceeds from disposal of business, net of cash sold	56,200,000
Deferred consideration - seller's note	175,000,000.0
Paid-in-kind interest	88,000,000
Deferred compensation - earnout payments	178,000,000.0
Fair value of debt instrument	$ 34,900,000
Payment in kind, annual interest rate	0.085
Customer relationships | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of intangible assets				14,400,000
Customer relationships | Grass Valley | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of intangible assets			14,400,000
Trademarks | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of intangible assets				$ 1,600,000
Trademarks | Grass Valley | Discontinued Operations, Held-for-sale
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Impairment of intangible assets			$ 1,600,000