Condensed Consolidated Statement Of Stockholders' Equity (Parenthetical)	9 Months Ended
Sep. 30, 2011
Condensed Consolidated Statement Of Stockholders' Equity [Abstract]
Issuance of common stock, shares	63,290
Issuance of deferred stock units, shares	47,506
Purchase of treasury stock	33,856

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

-Section 04

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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
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