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Fair Value Measurements - Quantitative Information (Details) (Discounted cash flow, USD $) In Millions, unless otherwise specified |  |  | 3 Months Ended |  |  | 3 Months Ended
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2014 Contingent payment arrangements [Member] | Dec. 31, 2013 Contingent payment arrangements [Member] | Mar. 31, 2014 Contingent payment arrangements [Member] Minimum | Mar. 31, 2013 Contingent payment arrangements [Member] Minimum | Mar. 31, 2014 Contingent payment arrangements [Member] Maximum | Mar. 31, 2013 Contingent payment arrangements [Member] Maximum | Mar. 31, 2013 Affiliate equity repurchase obligations [Member] | Mar. 31, 2014 Affiliate equity repurchase obligations [Member] | Dec. 31, 2013 Affiliate equity repurchase obligations [Member] | Mar. 31, 2014 Affiliate equity repurchase obligations [Member] Minimum | Mar. 31, 2014 Affiliate equity repurchase obligations [Member] Maximum
Quantitative information for Level 3 Fair Value Measurements Liabilities |  |  |  |  |  |  |  |  |  |  |
Fair value Liabilities | $ 53.2 | $ 50.2 |  |  |  |  |  | $ 58.3 | $ 4.0 |  |
Growth rate (as a percent) |  |  | 3.00% | 3.00% | 9.00% | 11.00% | 8.00% |  |  | 2.00% | 11.00%
Discount rate (as a percent) |  |  | 13.00% | 14.00% | 17.00% | 18.00% | 15.00% |  |  | 14.00% | 17.00%

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- Definition Represents percentage of assumed growth rates, used as an input to measure fair value. + References No definition available. + Details
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- Definition 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. + 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 (bbb) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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- Details
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- Definition Fair value of financial and nonfinancial obligations. + 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 (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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