Equity Incentive Plans, Equity Incentive Plans (Details)	6 Months Ended
Aug. 03, 2019 shares
2012 Plan [Member] \| Stock Options [Member]
Equity Incentive Plans [Abstract]
Vesting period	5 years
Expiration period	10 years
2012 Plan [Member] \| Stock Options [Member] \| Year 1 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	20.00%
2012 Plan [Member] \| Stock Options [Member] \| Year 2 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	20.00%
2012 Plan [Member] \| Stock Options [Member] \| Year 3 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	20.00%
2012 Plan [Member] \| Stock Options [Member] \| Year 4 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	20.00%
2012 Plan [Member] \| Stock Options [Member] \| Year 5 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	20.00%
2015 Plan [Member]
Equity Incentive Plans [Abstract]
Number of shares authorized for issuance (in shares)	5,250,000
Number of shares available for grant (in shares)	3,135,719
2015 Plan [Member] \| Stock Options [Member]
Equity Incentive Plans [Abstract]
Vesting period	4 years
Expiration period	10 years
2015 Plan [Member] \| Stock Options [Member] \| Year 1 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	25.00%
2015 Plan [Member] \| Stock Options [Member] \| Year 2 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	25.00%
2015 Plan [Member] \| Stock Options [Member] \| Year 3 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	25.00%
2015 Plan [Member] \| Stock Options [Member] \| Year 4 [Member]
Equity Incentive Plans [Abstract]
Vesting percentage	25.00%

No definition available.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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