Intangibles, net (Tables)

12 Months Ended

Dec. 31, 2017

Intangible Assets Net Excluding Goodwill [Abstract]

Identified Intangible Assets by Major Classification

Identified intangible assets by major classification consist of the following (in millions):

				Accumulated			Net Book
	Gross			Amortization			Value
December 31, 2015:
Trademarks and patents	$	85		$	(14	)	$	71
Customer relationships		103			(12	)		91
Other (covenant not to compete)		5			(4	)		1
Currency translation adjustments and other		(2	)		—			(2	)
Total identified intangibles	$	191		$	(30	)	$	161
December 31, 2016:
Trademarks and patents	$	105		$	(20	)	$	85
Customer relationships		125			(22	)		103
Other (covenant not to compete)		11			(6	)		5
Currency translation adjustments and other		(11	)		2			(9	)
Total identified intangibles	$	230		$	(46	)	$	184
December 31, 2017:
Trademarks and patents	$	103		$	(26	)	$	77
Customer relationships		117			(34	)		83
Other (covenant not to compete)		11			(9	)		2
Currency translation adjustments and other		6			(2	)		4
Total identified intangibles	$	237		$	(71	)	$	166

Schedule of Estimated Amortization of Intangible Assets

Amortization expense was $22 million, $21 million and $13 million for the years ended December 31, 2017, 2016, and 2015, respectively. The following table represents the total estimated amortization of intangible assets for the five succeeding years (in millions): 

For the Year Ending December 31	Estimated Amortization Expense
2018	$	20
2019		19
2020		19
2021		18
2022		18