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Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Jan. 26, 2020 | Jan. 27, 2019 | Jan. 28, 2018
Accounting Policies [Abstract] |  |  |
Aggregate net investments under cost method of accounting | $ 19,400 | $ 16,700 |
Total equity method investments | 3,300 | 2,700 |
Impairment of investments | $ (1,211) | (30,000) | $ (4,250)
Percent of realizable undiscounted cash flows used to determine useful life of acquired finite-lived intangible assets, minimum | 90.00% |  |
Advertising costs | $ 900 | 600 | 600
Recoveries from nonrecurring engineering services | $ 8,400 | $ 4,400 | $ 5,400

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- Definition Acquired Finite-Lived Intangible Assets, Percentage of Realizable Undiscounted Cash Flows Used to Determine Useful Life, Minimum + References No definition available. + Details
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- Definition Research and Development, Recoveries from Engineering Services + References No definition available. + Details
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- Definition Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 720 -SubTopic 35 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6420018&loc=d3e36677-107848 + Details
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- Definition This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 25 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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