Equity Incentive Plans, Stock Option Activity (Details) - Stock Options [Member] - $ / shares	6 Months Ended
Aug. 03, 2019
Number of Options [Roll Forward]
Outstanding at beginning of period (in shares)	3,746,422
Granted (in shares)	289,729
Forfeited (in shares)	(18,813)
Exercised (in shares)	(535,891)
Outstanding at end of period (in shares)	3,481,447
Exercisable at end of period (in shares)	2,553,853
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (in dollars per share)	$ 15.29
Granted (in dollars per share)	80.05
Forfeited (in dollars per share)	62.05
Exercised (in dollars per share)	14.13
Outstanding at end of period (in dollars per share)	20.61
Exercisable at end of period (in dollars per share)	$ 10.87
Weighted Average Remaining Contractual Term [Abstract]
Outstanding at end of period	5 years 2 months 12 days
Exercisable at end of period	4 years 1 month 6 days

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

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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 option holders acquired shares when converting their stock options into shares.

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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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Number of share options (or share units) exercised during the current period.

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