Fair Value Measurements (Details 6) (Contingent consideration, USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Changes in Level 3 liabilities measured at fair value on recurring basis
Beginning balance	$ 42,624	$ 51,555
Fair value adjustments included in other income (expense), net	1,380	142
Ending balance	$ 44,004	$ 51,697
Minimum
Changes in Level 3 liabilities measured at fair value on recurring basis
Fair value inputs, discount rate (in hundredths)	14.00%
Maximum
Changes in Level 3 liabilities measured at fair value on recurring basis
Fair value inputs, discount rate (in hundredths)	18.00%

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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- Details

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- Definition

Amount of gain (loss) recognized in earnings, arising from liabilities measured at fair value on a recurring basis using unobservable inputs (level 3).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 157

-Paragraph 32

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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

+ Details

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- Definition

This element represents a liability measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

+ Details

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