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Investments - Narrative (Details) - USD ($) $ in Thousands | Apr. 29, 2018 | Jan. 28, 2018
--- | --- | ---
Other Assets [Member] |  |
Investment [Line Items] |  |
Total investment in a private entity | $ 30,000 |
Restricted deposits | 3,000 |
Agency Securities [Member] | Level 1 [Member] |  |
Investment [Line Items] |  |
Investments in money market funds | $ 30,004 | $ 0

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