Goodwill and Acquired Intangible Assets

The change in the carrying amount of goodwill for the nine months ended September 30, 2018 was as follows (in thousands):



Balance as of January 1, 2018	$	1,498,688
Measurement period adjustments	(6,667		)
Foreign currency translation	(3,153		)
Balance as of September 30, 2018	$	1,488,868

The Company tests goodwill for impairment at least annually. Through the date the consolidated financial statements were issued, no triggering events had occurred that would indicate a potential impairment exists.

Acquired intangible assets that are subject to amortization consisted of the following as of September 30, 2018 and December 31, 2017 (in thousands):



	September 30, 2018							December 31, 2017
	Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization			Net Carrying Amount
Completed technology	$	145,091	$	(77,512	)	$	67,579	$	145,091	$	(65,283	)	$	79,808
Customer-related intangible assets	245,710		(140,798		)	104,912		245,310		(128,835		)	116,475
Non-compete agreements	700		(256		)	444		4,710		(3,975		)	735
Trademarks and trade names	7,200		(3,495		)	3,705		7,200		(2,959		)	4,241
Acquired license rights	490		(490		)	—		490		(490		)	—
Total	$	399,191	$	(222,551	)	$	176,640	$	402,801	$	(201,542	)	$	201,259

Aggregate expense related to amortization of acquired intangible assets for the three and nine months ended September 30, 2018 was $8.3 million and $25.0 million, respectively. Aggregate expense related to amortization of acquired intangible assets for the three and nine months ended September 30, 2017 was $7.8 million and $23.1 million, respectively. Based on the Company’s acquired intangible assets as of September 30, 2018, aggregate expense related to amortization of acquired intangible assets is expected to be $8.3 million for the remainder of 2018, and $36.6 million, $33.9 million, $28.0 million and $22.4 million for 2019, 2020, 2021 and 2022, respectively.