Debt (Tables)

9 Months Ended

Sep. 30, 2019

Debt Disclosure [Abstract]

Schedule of deferred revenue, by arrangement

The following table shows the activity within the liability related to sale of future royalties during the nine months ended September 30, 2019 (in thousands):

Carrying value of liability related to sale of future royalties at December 31, 2018	$	221,295
Interest expense recognized	30,022
Carrying value of liability related to sale of future royalties at September 30, 2019	$	251,317