INTANGIBLE ASSETS

9 Months Ended

Sep. 30, 2020

Goodwill and Intangible Assets Disclosure [Abstract]

INTANGIBLE ASSETS

INTANGIBLE ASSETS

As of September 30, 2020, the net book value of amortizable intangible assets was approximately $154.2 million.

The following table sets forth amortizable intangible assets as of September 30, 2020 and December 31, 2019 (in thousands):

	September 30, 2020		December 31, 2019
Finite-lived intangible assets	$	259,537	$	245,802
Less: accumulated amortization	(105,320)		(88,602)
Net carrying value	$	154,217	$	157,200

The following table summarizes amortization expense for the three and nine months ended September 30, 2020 and 2019 (in thousands):

	Three Months Ended September 30,				Nine Months Ended September 30,
	2020		2019		2020		2019
Research and development	$	292	$	292	$	870	$	866
Selling, general and administrative	5,731		4,715		15,612		13,728
Total amortization expense	$	6,023	$	5,007	$	16,482	$	14,594