Contingent Consideration (Details) (USD $) In Thousands	1 Months Ended	3 Months Ended	9 Months Ended
Apr. 30, 2011	Jun. 30, 2011	Sep. 30, 2011
Contingent Consideration
Contingent consideration payment due in 2011	$ 40,000
Maximum aggregate undiscounted amount of contingent consideration			59,000
Remaining contingent consideration liability adjusted through operating income			17,813
Changes in net income due to adjustment of remaining contingent consideration liability		$ 11,200	$ 11,200

Amount of potential cash payments that could result from the contingent consideration arrangement.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141

-Paragraph 51

-Subparagraph f

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant