Goodwill and Intangible Assets

Changes in the carrying amount of goodwill for the nine months ended September 30, 2018 are as follows:



(in thousands)	Goodwill
Balance as of December 31, 2017	$	9,402
Measurement period adjustment	(2,807		)
Foreign currency translation	(67		)
Balance as of September 30, 2018	$	6,528

See Note 3 for a description of the measurement period adjustment.

The Company’s intangible assets at September 30, 2018 and December 31, 2017 consisted of the following:



	September 30, 2018							December 31, 2017
(in thousands)	Gross Carrying Amount		Accumulated Amortization			Net		Gross Carrying Amount		Accumulated Amortization			Net
Other intangible assets:
Developed technology	$	759,367	$	(124,335	)	$	635,032	$	759,374	$	(94,886	)	$	664,488
In-process research and development	39,000		(4,514		)	34,486		39,000		(2,889		)	36,111
Trade name	29,580		—			29,580		29,816		—			29,816
Service provider network	2,000		—			2,000		2,000		—			2,000
Customer relationships	20,409		(2,338		)	18,071		20,306		(806		)	19,500
Software	8,496		(2,075		)	6,421		1,274		(404		)	870
Software not yet placed in service	—		—			—		5,022					5,022
Other	100		(37		)	63		100		(25		)	75
Total intangible assets	$	858,952	$	(133,299	)	$	725,653	$	856,892	$	(99,010	)	$	757,882

At September 30, 2018, the weighted-average amortization period remaining for the finite-lived intangible assets was 16.7 years. At September 30, 2018, the weighted-average amortization periods remaining for developed technology, customer relationships, in-process R&D, software and other was 16.6, 20.9, 16.0, 2.3, and 3.8 years, respectively.

Estimated annual amortization expense for finite-lived intangible assets, excluding amounts in Work in Progress, subsequent to September 30, 2018 is as follows:



(in thousands)	Amount
2018 (remaining)	$	12,062
2019	46,113
2020	45,996
2021	43,705
2022	43,235
Thereafter	502,962
Total	$	694,073