Interest Expense (Tables)

9 Months Ended

Sep. 30, 2020

Other Income and Expenses [Abstract]

Schedule of interest expense

Interest expense consists of the following (dollars in thousands):

	Three Months ended September 30,				Nine Months ended September 30,
	2020		2019		2020		2019
	(unaudited)				(unaudited)
Interest expense	$	(4,945)	$	(4,546)	$	(14,430)	$	(13,518)
Interest expense on nonrecourse liability related to sale of future royalties	(1,143)		(1,116)		(3,228)		(3,412)
Total	$	(6,088)	$	(5,662)	$	(17,658)	$	(16,930)