Long-term Debt (Narrative) (Details 2) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Interest rate		5.75%
Convertible Notes
Debt outstanding		$ 16.5		$ 16.5
Month and year of issue		August 2007
Number of interest payments, per year		4
Effective interest rate		5.90%
Debt amount originally issued		50.0
Net proceeds upon original issuance		49.4
Deferred debt issuance costs amortization period, in years		7 years
Interest accrued		0		0
Debt due date		August 7, 2014
Conversion price of 5.75% convertible notes, per share				$ 5.44
Conversion of 5.75% convertible notes	30.6		33.5
Conversion of 5.75% convertible notes, shares	5,620,445		6,149,727
Sensipar and Mimpara-Secured Non-recourse Debt Class A Notes
Debt outstanding		0		0
Month and year of issue		December 2004
Interest rate		8.00%
Debt amount originally issued		175.0
Net proceeds upon original issuance		169.3
Interest accrued		0		0
Debt due date		March 30, 2017
Sensipar and Mimpara-Secured Non-recourse Debt Class B Notes
Debt outstanding		0		0
Month and year of issue		August 2007
Interest rate		15.50%
Debt amount originally issued		100.0
Net proceeds upon original issuance		97.0
Interest accrued		0		0
Debt due date		March 30, 2017
Sensipar and Mimpara-Secured Non-recourse Debt Sensipar Notes
Debt outstanding		92.3		126.8
Debt classified as current		6.0		18.1
Month and year of issue		September 2011
Month and year of amendment		June 2012
Interest rate		9.00%
Effective interest rate		9.00%
Debt amount originally issued		145.0
Net proceeds upon original issuance		144.9
Interest accrued		1.0		1.4
Quarterly limit of royalty offset of the royalty advance		8.0
Preotact-Secured Non-recourse Debt
Debt outstanding		45.5		48.3
Month and year of issue		July 2007
Interest rate		11.10%
Effective interest rate		11.10%
Debt amount originally issued		50.0
Net proceeds upon original issuance		50.0
Interest accrued		0.1		0.7
Interest and principal paid to date		42.5
REGPARA-Secured Non-recourse Debt
Debt outstanding		36.3		36.3
Month and year of issue		February 2010
Interest rate		19.10%
Effective interest rate		19.10%
Debt amount originally issued		38.4
Net proceeds upon original issuance		38.4
Deferred debt issuance costs amortization period, in years		10 years
Interest accrued		1.7		4.0
Interest and principal paid to date		$ 15.6