Fair Value Measurements Fair Value Measurements - Goodwill (Details) (Goodwill, Income approach valuation technique)	6 Months Ended
Jun. 30, 2012
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discounted forecasted cash flows period	10 years
Discount rate	17.60%
Terminal growth rate	3.50%
Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Revenue growth rates in 2012 through 2014	30.00%
Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Revenue growth rates in 2012 through 2014	35.00%

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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

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

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