Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Nominal or face amount used to calculate payment on derivative.

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The difference between the book value and the sale price of options, swaps, futures, forward contracts, and other derivative instruments. This element refers to the gain (loss) included in earnings.

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The charge against earnings resulting from the write down of long lived assets other than goodwill due to the difference between the carrying value and lower fair value.

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Fair Value of Assets and Liabilities - Narrative (Details) - USD ($)		3 Months Ended			6 Months Ended
	Mar. 23, 2020	Jun. 27, 2020	Mar. 28, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	Dec. 28, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges		$ 33,841,000		$ 0	$ 36,078,000	$ 0
Investments in equity securities		12,899,000			12,899,000		$ 12,969,000
Notional amount of derivatives							16,000,000.0
Gain on derivatives	$ 200,000
Other Expense (Income)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges						$ 2,800,000
Investments in equity securities		$ 400,000			$ 400,000		$ 400,000
Patents
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges			$ 300,000
Land and Building
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Impairment charges			$ 1,900,000