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Fair Value Measurements (Details Textual 1) (USD $) In Millions, unless otherwise specified | 3 Months Ended |
--- | --- | ---
Mar. 31, 2014 | Dec. 31, 2013
Business Acquisition, Contingent Consideration [Line Items] |  |
Asset impairment charges | $ 0 |
Changed in valuation techniques | 0 |
Percentage of venture capital investments to assets | 0.20% | 0.20%
Other Liabilities, Non Current |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Contingent consideration obligations | $ 254.1 | $ 251.9
6.875% Senior Notes due 2018 |  |
Business Acquisition, Contingent Consideration [Line Items] |  |
Stated rate on debt | 6.875% |

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