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Indebtedness (Details Textual) | 12 Months Ended |  | 0 Months Ended |  | 1 Months Ended |  |  |  |  |  |  |
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Dec. 31, 2013 USD ($) | Dec. 31, 2012 USD ($) | Dec. 31, 2011 USD ($) | Mar. 31, 2013 USD ($) | Mar. 01, 2013 6.0% Senior notes due 2013 USD ($) | Mar. 04, 2008 6.0% Senior notes due 2013 USD ($) | Dec. 31, 2008 6.875% Senior notes due 2018 USD ($) | Dec. 31, 2013 6.875% Senior notes due 2018 USD ($) | Dec. 31, 2012 6.875% Senior notes due 2018 USD ($) | Mar. 04, 2008 6.875% Senior notes due 2018 USD ($) | Dec. 31, 2013 Note payable to Fumedica USD ($) | Dec. 31, 2013 Note payable to Fumedica CHF | Dec. 31, 2012 Note payable to Fumedica USD ($) | Dec. 31, 2012 Note payable to Fumedica CHF | Dec. 31, 2006 Note payable to Fumedica CHF | Dec. 31, 2012 Cambridge Leases USD ($)
Debt Instrument |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal amount of senior notes |  |  |  |  |  | $ 450,000,000 |  |  |  | $ 550,000,000 |  |  |  |  |  |
Interest rate on senior notes |  |  |  |  |  | 6.00% |  |  |  | 6.875% |  |  |  |  |  |
Redemption percentage par value of senior notes |  |  |  |  |  | 99.886% |  |  |  | 99.184% |  |  |  |  |  |
Percentage of redemption of notes | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increased carrying amount of interest rate swap |  |  |  |  |  |  | 62,800,000 |  |  |  |  |  |  |  |  |
Interest to be amortized on debt | 32,400,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repayments of borrowings | 452,340,000 | 2,428,000 | 11,459,000 |  | 450,000,000 |  |  |  |  |  |  |  |  |  |  |
Notes payable and other financing arrangements | 567,900,000 |  |  |  |  |  |  | 580,100,000 | 586,400,000 |  | 12,300,000 |  | 14,500,000 |  | 61,400,000 |
Present value of notes payable |  |  |  |  |  |  |  |  |  |  | 15,800,000 | 14,000,000 | 17,900,000 | 16,400,000 |  |
Senior unsecured revolving credit facility maximum borrowing capacity |  |  |  | 750,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, amount outstanding | 0 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Remaining obligation of financing arrangements |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 86,500,000
Debt Instrument, Payment Terms | 100% of the principal amount plus accrued interest and a specified make-whole amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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