Fair Value of Assets and Liabilities - Narratives (Details) - USD ($)	3 Months Ended						12 Months Ended
	Sep. 26, 2020	Jun. 27, 2020	Mar. 28, 2020	Dec. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Impairment charges	$ 100,000			$ 4,200,000	$ 200,000	$ 2,800,000	$ 36,078,000	$ 322,000	$ 2,218,000
Investments in equity securities				12,969,000			19,186,000	12,969,000
Gain (loss) on sale of derivatives							200,000
Other asset impairment charges		$ 33,800,000	$ 1,900,000
Other Assets
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Investments in equity securities				400,000			500,000	400,000
Other Expense
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Impairment charges							$ 100,000	7,300,000
Patents
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Other asset impairment charges			$ 300,000
Foreign Exchange Forward
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Notional value				$ 16,000,000.0				$ 16,000,000.0