Discontinued Operations (Details) $ in Thousands		3 Months Ended			6 Months Ended
	Jul. 02, 2020 USD ($)	Jul. 04, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jun. 28, 2020 USD ($)	Jul. 04, 2021 USD ($)	Jun. 28, 2020 USD ($)
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from disposal of business, net of cash sold					$ 10,798	$ 0
Asset impairment charges					6,995	113,007
Capital expenditure, discontinued operations				$ 8,500		16,400
Stock-based compensation, income				0		900
Grass Valley
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Accrued interest		$ 4,000			$ 7,700
Equity interest in divested business	$ 3,000
Equity interest in divested business, percentage	9.00%
Proceeds from sale and maturity of marketable securities			$ 2,700
Asset impairment charges				$ 89,800		$ 113,000
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
Proceeds from disposal of business, net of cash sold	56,200
Deferred consideration - seller's note	175,000
Paid-in-kind interest	88,000
Deferred compensation - earnout payments	$ 178,000
Payment in kind, annual interest rate	0.085
Fair value of note	$ 34,900