Takeda Termination and Transition Agreement (Narrative) (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Mar. 31, 2013
Takeda Termination And Transition Agreement Narrative Details
Shares of Common Stock issued	6.1	0	0
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	0		16,600,000
PTH raw materials	17,100,000	0		17,100,000
Revestive product rights	20,700,000
Estimated useful life of agreement	12 years
Revestive products rights amortization expense	1,400,000
Estimated annual amortization for each of the next five years	$ 1,800,000