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Investments - Narrative (Details) - USD ($) $ in Thousands | Oct. 29, 2017 | Jan. 29, 2017
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Other Assets [Member] |  |
Investment [Line Items] |  |
Total investment in a private entity | $ 25,000 |
Restricted deposits | 5,000 |
Agency Securities [Member] | Level 1 [Member] |  |
Investment [Line Items] |  |
Investments in money market funds | $ 10,126 | $ 16,945

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