Summary of Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2017

Accounting Policies [Abstract]

Redeemable Noncontrolling Interests

The following is a rollforward of activity in our redeemable noncontrolling interests for the years ending December 31, 2017, 2016 and 2015, respectively:

	2017			2016			2015
	(Millions)
Balance January 1	$	40		$	41		$	34
Net income attributable to redeemable noncontrolling interests	36			36			32
Other comprehensive income (loss)	3			(2		)	(1		)
Dividends declared	(37		)	(35		)	(24		)
Balance December 31	$	42		$	40		$	41

Inventories by Major Classification

Inventories

At December 31, 2017 and 2016, inventory by major classification was as follows:

	2017		2016
	(Millions)
Finished goods	$	349	$	284
Work in process	268		245
Raw materials	178		137
Materials and supplies	74		64
	$	869	$	730

Changes in Net Carrying Amount of Goodwill

The changes in the net carrying amount of goodwill for the years ended December 31, 2017, 2016 and 2015 were as follows:

	Clean Air Division						Ride Performance Division
	North America		Europe and South America		Asia Pacific		North America		Europe and South America			Asia Pacific		Total
(Millions)
Balance at December 31, 2015	$	14	$	11	$	—	$	10	$	11		$	14	$	60
Translation Adjustment	—		—		—		—		(3		)	—		(3		)
Balance at December 31, 2016	14		11		—		10		11			11		57
Translation Adjustment	—		1		—		—		—			2		3
Goodwill Impairment Charge	—		—		—		—		(11		)	—		(11		)
Balance at December 31, 2017	14		12		—		10		—			13		49

Carrying Amount and Accumulated Amortization of Finite Useful Life Intangible Assets

The carrying amount and accumulated amortization of our finite useful life intangible assets were as follows:

	December 31, 2017					December 31, 2016
	Gross Carrying Value		Accumulated Amortization			Gross Carrying Value		Accumulated Amortization
	(Millions)					(Millions)
Customer contract	$	8	$	(5	)	$	8	$	(5	)
Patents	1		(1		)	1		(1		)
Technology rights	29		(23		)	29		(21		)
Other	15		(2		)	9		(1		)
Total	$	53	$	(31	)	$	47	$	(28	)

Property, Plant and Equipment

At December 31, 2017 and 2016, plant, property, and equipment, at cost, by major category were as follows:

	2017		2016
	(Millions)
Land, buildings, and improvements	$	635	$	568
Machinery and equipment	2,983		2,638
Other, including construction in progress	390		342
	$	4,008	$	3,548