INTANGIBLE ASSETS AND GOODWILL

12 Months Ended

Dec. 31, 2019

Goodwill and Intangible Assets Disclosure [Abstract]

The changes in the carrying amount of intangible assets and goodwill were as follows:



		As of December 31, 2019						As of December 31, 2018
	Estimated Useful Lives	Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount		Gross Carrying Amount		Accumulated Amortization		Net Carrying Amount
	(Years)	(in millions)						(in millions)
Amortized intangible assets:
Patents and developed technology	6-12	$	134	$	118	$	16	$	134	$	107	$	27
Customer relationships	3-10	114		101		13		110		94		16
Trade names	5-20	46		24		22		46		22		24
Total		294		243		51		290		223		67
Unamortized intangible assets:
Trade names	—	2		—		2		2		—		2
Goodwill	—	7		—		7		7		—		7
Total		$	303	$	243	$	60	$	299	$	223	$	76

Estimated amortization expense for the years ending December 31, 2019 through 2023 is presented below:



	Year Ending December 31,
	2020		2021		2022		2023		2024
	(in millions)
Estimated amortization expense	$	17	$	12	$	2	$	2	$	2

A roll-forward of the gross carrying amounts of intangible assets for the years ended December 31, 2019 and 2018 is presented below.



	2019		2018
	(in millions)
Balance at January 1	$	299	$	287
Acquisitions	4		14
Foreign currency translation	—		(2		)
Balance at December 31	$	303	$	299

A roll-forward of the accumulated amortization for the years ended December 31, 2019 and 2018 is presented below:



	2019		2018
	(in millions)
Balance at January 1	$	223	$	205
Amortization	18		20
Foreign currency translation	2		(2		)
Balance at December 31	$	243	$	223

During the year ended December 31, 2019, the Company recorded impairment of $3 million related to intangible assets which is included in amortization expense. No intangible asset impairments were recorded in 2018 or 2017.