Goodwill and Intangible Assets, Net

9 Months Ended

Sep. 30, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

ngible Assets, Net

Intangible assets consist primarily of developed technology and patent licenses from business combinations. Acquired intangibles are amortized on a straight-line basis over the respective estimated useful lives of the assets.

The carrying values of intangible assets are as follows (in thousands, except for years):



					September 30, 2019
	Weighted Average Life (Years)	Weighted Average Remaining Life (Years)	Cost		Accumulated Amortization			Net Book Value
Developed technology	5	3.0	$	26,356	$	(8,570	)	$	17,786
Patent licenses	14	4.9	1,387		(897		)	490
Total intangibles subject to amortization			$	27,743	$	(9,467	)	18,276
Intangible assets not subject to amortization								40
Total intangible assets, net								$	18,316

					December 31, 2018
	Weighted Average Life (Years)	Weighted Average Remaining Life (Years)	Cost		Accumulated Amortization			Net Book Value
Developed technology	5	3.8	$	25,456	$	(4,085	)	$	21,371
Patent Licenses	14	5.9	1,387		(822		)	565
Total intangibles subject to amortization			$	26,843	$	(4,907	)	21,936
Intangible assets not subject to amortization								40
Total intangible assets, net								$	21,976

Intangible asset amortization expense was $1.5 million and $0.9 million for the three months ended September 30, 2019 and 2018, respectively, and $4.6 million and $2.4 million for the nine months ended September 30, 2019 and 2018, respectively.

As of September 30, 2019, the Company expects amortization expense in future periods to be as follows (in thousands):



	Amortization Expense
2019 (remaining three months)	$	1,521
2020	6,081
2021	6,081
2022	4,427
2023	100
2024 and thereafter	66
Total expected future amortization expense	$	18,276