Consolidated Statement Of Changes In Shareholders' Equity (Parenthetical) In Thousands, unless otherwise specified	9 Months Ended
Jan. 28, 2012
Consolidated Statement Of Changes In Shareholders' Equity [Abstract]
Stock options exercised, shares	89
Treasury stock acquired, shares	127

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section 50

-Paragraph 2

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Section S99

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Balance Type:	na
Period Type:	duration