Intangible assets

6 Months Ended

Jun. 30, 2020

Intangible assets

Intangible assets

7. INTANGIBLE ASSETS

	June 30, 2020						December 31, 2019
	Gross carrying value		Accumulated amortization		Net carrying value		Gross carrying value		Accumulated amortization		Net carrying value
Customer relationships	$	615	$	(124)	$	491	$	615	$	(102)	$	513
Backlog		330		(265)		65		330		(217)		113
Technologies		320		(177)		143		320		(144)		176
Software		254		(103)		151		213		(83)		130
Image library		80		(54)		26		80		(48)		32
Trade names and other		37		(12)		25		37		(10)		27
Intangible assets	$	1,636	$	(735)	$	901	$	1,595	$	(604)	$	991

Amortization expense related to intangible assets was $66 million and $68 million, and $132 million and $135 million for the three and six months ended June 30, 2020 and June 30, 2019, respectively.