Share-Based Compensation (Schedule of Stock options Outstanding and Exercisable) (Details) - Employee Stock Option [Member] - $ / shares	12 Months Ended
Jan. 28, 2017	Jan. 30, 2016
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	150,540	301,295
Weighted- Average Remaining Life (Years)	2 years 9 months 3 days
Weighted- Average Exercise Price	$ 20.25	$ 18.93
Number of Options	123,873
Weighted Average Remaining Life (Years)	2 years 1 month 6 days
Weighted- Average Exercise Price	$ 20.42
$3.33 - $8.07
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	28,250
Weighted- Average Remaining Life (Years)	2 years 10 months 2 days
Weighted- Average Exercise Price	$ 4.63
Number of Options	18,250
Weighted Average Remaining Life (Years)	3 years 2 months 23 days
Weighted- Average Exercise Price	$ 5.35
$8.08 - $14.60
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	33,875
Weighted- Average Remaining Life (Years)	4 years 18 days
Weighted- Average Exercise Price	$ 10.99
Number of Options	33,875
Weighted Average Remaining Life (Years)	4 years 18 days
Weighted- Average Exercise Price	$ 10.99
$14.61 - $24.82
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	24,500
Weighted- Average Remaining Life (Years)	2 years 4 months 20 days
Weighted- Average Exercise Price	$ 16.08
Number of Options	24,500
Weighted Average Remaining Life (Years)	2 years 4 months 20 days
Weighted- Average Exercise Price	$ 16.08
$24.83 - $32.22
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	16,667
Weighted- Average Remaining Life (Years)	8 years 18 days
Weighted- Average Exercise Price	$ 29.18
$32.23 - $35.25
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Number of Options	47,248
Weighted- Average Remaining Life (Years)	1 month 9 days
Weighted- Average Exercise Price	$ 35.25
Number of Options	47,248
Weighted Average Remaining Life (Years)	1 month 9 days
Weighted- Average Exercise Price	$ 35.25

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

+ References

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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