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Fair Value Measurements (Details 2) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012
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Summary of fair and carrying value of debt instruments |  |
Credit facility, amount outstanding | $ 0 | $ 0
Total fair value | 665.4 | 1,155.3
Notes Payable to Fumedica |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 17.5 | 20.0
6.0% Senior Notes due 2013 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | 0 | 453.7
6.875% Senior Notes due 2018 |  |
Summary of fair and carrying value of debt instruments |  |
Notes payable, fair value | $ 647.9 | $ 681.6

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- Definition Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13433-108611 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=28364263&loc=d3e13476-108611 + Details
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- Definition Amount borrowed under the credit facility as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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