Income Taxes - Reconciliation of Company's Unrecognized Tax Benefits, Excluding Interest and Penalties (Detail) - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Jan. 28, 2017  | 
Jan. 30, 2016  | 
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| Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued [Abstract] | ||
| Balance at beginning of the period | $ 2,262 | $ 1,414 | 
| Increase due to a current year position | 1,048 | 900 | 
| Decrease due to a prior period position | (5) | (52) | 
| Balance at the end of the period | $ 3,305 | $ 2,262 | 
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- Definition Amount of unrecognized tax benefits. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of decrease in unrecognized tax benefits resulting from tax positions taken in prior period tax returns. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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| X | ||||||||||
- References No definition available. 
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- Definition Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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