Goodwill and Intangible Assets

12 Months Ended

Dec. 31, 2023

Goodwill and Intangible Assets Disclosure [Abstract]

(8) Goodwill and Intangibles

Goodwill was $536.4 million and $515.6 million as of December 31, 2023 and December 31, 2022, respectively. There were no goodwill impairment charges in 2023, 2022 or 2021. The following table displays the changes in the gross carrying amount of goodwill:


	Amount
	(in thousands)


Balance at December 31, 2021	$	515,258
IntSights acquisition adjustments	373
Balance at December 31, 2022	$	515,631
Minerva acquisition	20,720
Balance at December 31, 2023	$	536,351

The following table presents details of our intangible assets which include acquired identifiable intangible assets and capitalized internal-use software costs:


	Weighted- Average Estimated Useful Life (years)	As of December 31, 2023						As of December 31, 2022
		Gross Carrying Amount		Accumulated Amortization		Net Book Value		Gross Carrying Amount		Accumulated Amortization		Net Book Value
		(in thousands)
Intangible assets subject to amortization:
Developed technology	5.4	$	135,355	$	(77,031)	$	58,324	$	122,555	$	(58,645)	$	63,910
Customer relationships	4.5	12,000		(7,755)		4,245		12,000		(5,146)		6,854
Trade names	3.1	2,619		(2,379)		240		2,619		(1,874)		745
Total acquired intangible assets		$	149,974	$	(87,164)	$	62,810	$	137,174	$	(65,665)	$	71,509
Internal-use software	3.0	55,371		(23,635)		31,736		43,002		(13,242)		29,760
Total intangible assets		$	205,345	$	(110,799)	$	94,546	$	180,176	$	(78,907)	$	101,269

Intangible assets are expensed on a straight-line basis over the useful life of the asset. Amortization expense was $31.9 million, $27.5 million and $21.2 million in 2023, 2022 and 2021, respectively.

Estimated future amortization expense of the acquired identifiable intangible assets and completed capitalized internal-use software costs as of December 31, 2023 was as follows (in thousands):


2024	$	30,880
2025	26,795
2026	17,220
2027	6,806
2028	1,600
2029 and thereafter	3,531
Total	$	86,832

The table above excludes the impact of $7.7 million of capitalized internal-use software costs for projects that have not been completed as of December 31, 2023, and therefore, we have not determined the useful life of the software, nor have all the costs associated with these projects been incurred. For the year ended December 31, 2023, we recorded a $3.5 million impairment of capitalized internal-use software costs to research and development expense in our consolidated statement of operations for projects that have been discontinued and will not be placed into service.