Fair Value Measurement (Debt Instruments) (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Debt instruments, fair value	$ 184,029	$ 184,752
Debt instruments, carrying value	163,180	175,847
Convertible Notes
Debt instruments, fair value	45,963	28,131
Debt instruments, carrying value	16,545	16,545
Sensipar Notes
Debt instruments, fair value	66,911	79,129
Debt instruments, carrying value	67,593	80,234
PTH 1-84-(Europe, CIS and Turkey)-Secured Debt
Debt instruments, fair value	30,097	28,605
Debt instruments, carrying value	42,790	42,816
Regpara-Secured Debt
Debt instruments, fair value	41,058	48,887
Debt instruments, carrying value	$ 36,252	$ 36,252