Takeda Termination and Transition Agreement (Narrative) (Details) (USD $)	6 Months Ended
	Jun. 30, 2013	Mar. 31, 2013
Takeda Termination And Transition Agreement Narrative Details
Shares of Common Stock issued	6,100,000
Value of Common Stock issued	$ 54,900,000
Future milestone payment in cash or common stock	30,000,000
Milestone payment trigger amount on worldwide net sales	750,000,000
Assets acquired:
Revestive raw materials		16,600,000
PTH raw materials		17,100,000
Revestive product rights	$ 20,700,000