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Fair Value of Assets and Liabilities - Narrative (Details) - USD ($) $ in Thousands |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | ---
Mar. 23, 2020 | Sep. 26, 2020 | Mar. 28, 2020 | Sep. 28, 2019 | Sep. 26, 2020 | Sep. 28, 2019 | Dec. 28, 2019
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |  |  |  |
Impairment charges |  | $ 0 |  | $ 322 | $ 36,078 | $ 322 |
Investments in equity securities |  | 15,042 |  |  | 15,042 |  | $ 12,969
Notional amount of derivatives |  |  |  |  |  |  | 16,000
Gain on derivatives | $ 200 |  |  |  |  |  |
Patents |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |  |  |  |
Impairment charges |  |  | $ 300 |  |  |  |
Land and Building |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |  |  |  |
Impairment charges |  |  | $ 1,900 |  |  |  |
Other Expense (Income) |  |  |  |  |  |  |
Fair Value, Balance Sheet Grouping, Financial Statement Captions |  |  |  |  |  |  |
Impairment charges |  | 100 |  |  |  | $ 2,800 |
Investments in equity securities |  | $ 500 |  |  | $ 500 |  | $ 400

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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228 + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3602-108585 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.13(h)) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 + Details
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