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Investments - Narrative (Details) - USD ($) $ in Thousands | Jan. 28, 2018 | Jan. 29, 2017
--- | --- | ---
Investment [Line Items] |  |
Cash equivalents | $ 1,960 | $ 1,425
Total equity investment in privately traded companies | 38,100 | 27,100
Other assets |  |
Investment [Line Items] |  |
Total equity investment in privately traded companies | 28,000 |
Restricted deposit | 5,000 |
Level 1 | Cash equivalents |  |
Investment [Line Items] |  |
Cash equivalents | 0 | 16,945
Convertible debt |  |
Investment [Line Items] |  |
Cash equivalents | $ 1,960 | $ 1,425

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