Intangible Assets

6 Months Ended

Jun. 30, 2019

Goodwill And Intangible Assets Disclosure [Abstract]

Intangible Assets

7.   Intangible Assets

The gross book value, accumulated amortization and net book value of intangible assets were as follows:

	(Stated in millions)
	Jun. 30, 2019						Dec. 31, 2018
	Gross		Accumulated		Net Book		Gross		Accumulated		Net Book
	Book Value		Amortization		Value		Book Value		Amortization		Value
Customer relationships	$	4,750	$	1,315	$	3,435	$	4,768	$	1,243	$	3,525
Technology/technical know-how		3,452		1,325		2,127		3,494		1,246		2,248
Tradenames		2,799		679		2,120		2,799		628		2,171
Other		1,394		591		803		1,404		621		783
	$	12,395	$	3,910	$	8,485	$	12,465	$	3,738	$	8,727

Amortization expense charged to income was as follows:

(Stated in millions)
	2019		2018
Second Quarter	$	164	$	174
Six Months	$	324	$	339

Based on the net book value of intangible assets at June 30, 2019, amortization charged to income for the subsequent five years is estimated to be: remaining two quarters of 2019—$347 million; 2020—$663 million; 2021—$633 million; 2022—$623 million; 2023—$612 million; and 2024—$569 million.