INTANGIBLE ASSETS

12 Months Ended

Dec. 31, 2023

5. INTANGIBLE ASSETS

Intangible assets on the Company’s consolidated balance sheets consist of the following (in thousands):


	Weighted Average	December 31, 2023						December 31, 2022
	Amortization	Gross		Accumulated		Net Book		Gross		Accumulated		Net Book
	Period	Amount		Amortization		Value		Amount		Amortization		Value
Customer lists	14.3 years	$	116,831	$	(42,421)	$	74,410	$	112,378	$	(34,377)	$	78,001
Trade name	13.9 years		15,572		(7,916)		7,656		15,320		(6,900)		8,420
Design and technologies	10.6 years		41,480		(12,173)		29,307		41,212		(8,558)		32,654
Total		$	173,883	$	(62,510)	$	111,373	$	168,910	$	(49,835)	$	119,075

Intangible assets resulting from the 2023 acquisition of Sierramotion was $4,100 and from the 2022 acquisitions of FPH, ThinGap, and Airex were $28,611 (Note 2). The intangible assets acquired consist of customer lists, technology, and trade names.

Total amortization expense for intangible assets for the years 2023, 2022 and 2021 was $12,313, $11,169 and $6,245, respectively.

Estimated amortization expense for intangible assets is as follows (in thousands):


Year ending December 31,	Total
	Estimated
	Amortization Expense
2024	$	12,216
2025		12,200
2026		12,103
2027		11,659
2028		10,929
Thereafter		52,266
Total estimated amortization expense	$	111,373