Intangible Assets

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Assets

6. Intangible Assets

Intangible assets as of December 31, 2023 and 2022 are comprised of the following (in thousands):

	December 31, 2023
	Gross amount		Accumulated amortization			Net amount
Intellectual property assets	$	9,150	$	(7,613	)	$	1,537
Intangible assets	$	9,150	$	(7,613	)	$	1,537

	December 31, 2022
	Gross amount		Accumulated amortization			Net amount
Intellectual property assets	$	9,111	$	(7,181	)	$	1,930
Intangible assets	$	9,111	$	(7,181	)	$	1,930

Aggregate amortization expense for intangible assets totaled $616 thousand, $683 thousand and $744 thousand for the years ended December 31, 2023, 2022 and 2021, respectively.

The aggregate amortization expense of intangible assets for the next five years are estimated to be $490 thousand, $375 thousand, $272 thousand, $186 thousand and $120 thousand for the years ended December 31, 2024, 2025, 2026, 2027 and 2028, respectively.