Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Apr. 29, 2017	Apr. 30, 2016
Numerator:
Net income	$ 10,049	$ 7,326
Denominator:
Weighted average common shares outstanding-basic	60,366,768	50,836,727
Effect of dilutive securities:
Stock options and restricted stock units	1,898,480	1,770,767
Weighted average common shares outstanding-diluted	62,265,248	52,607,494
Per common share:
Basic net income per common share	$ 0.17	$ 0.14
Diluted net income per common share	$ 0.16	$ 0.14

The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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