Condensed Consolidated Statement Of Stockholders' Equity (Parenthetical)	3 Months Ended
Mar. 31, 2013
Condensed Consolidated Statement Of Stockholders' Equity [Abstract]
Issuance of common stock, shares	217,879
Issuance of deferred stock units, shares	3,776

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 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.28,29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (c)(1)(iv)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 29, 30

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

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-Section S99

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-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

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Balance Type:	na
Period Type:	duration