Equity Award Plans - Stock Option Activity for All Plans (Details) $ / shares in Units, shares in Thousands, $ in Thousands	9 Months Ended
Nov. 03, 2018 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding Stock Options, Beginning balance \| shares	544
Outstanding Stock Options, Granted \| shares	464
Outstanding Stock Options, Forfeited \| shares	(483)
Outstanding Stock Options, Ending balance \| shares	525
Outstanding Stock Options, Exercisable \| shares	179
Weighted Average Exercise Price, Beginning balance \| $ / shares	$ 11.26
Weighted Average Exercise Price, Granted \| $ / shares	3.06
Weighted Average Exercise Price, Forfeited \| $ / shares	8.44
Weighted Average Exercise Price, Ending balance \| $ / shares	6.62
Weighted Average Exercise Price, Exercisable \| $ / shares	$ 11.35
Weighted Average Remaining Life, Outstanding	8 years 4 months 24 days
Weighted Average Remaining Life, Exercisable	6 years 7 months 6 days
Aggregate Intrinsic Value, Ending balance \| $	$ 598

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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