Stock Based Compensation (Details Textuals) (USD $)	9 Months Ended
Sep. 30, 2011
Stock Options [Member]
Stock Based Compensation (Textuals) [Abstract]
Weighted-average fair value of stock option awards granted	$ 14.70
Restricted Stock [Member]
Stock Based Compensation (Textuals) [Abstract]
Weighted-average fair value of stock option awards granted	$ 29.14
Performance Share Awards [Member]
Stock Based Compensation (Textuals) [Abstract]
Weighted-average fair value of stock option awards granted	$ 43.68

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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

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Namespace Prefix:	us-gaap
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration