Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accounts Payable and Accrued Expenses
Accounts payable	$ 7,502	$ 6,995
Accrued expenses:
Sales related (royalties, rebates and fees)	52,832	38,095
Payroll related	31,437	28,019
Research related	7,635	7,500
Other	4,027	4,773
Total accrued expenses	95,931	78,387
Total accounts payable and accrued expenses	$ 103,433	$ 85,382