The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Other Intangible Assets - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Goodwill [Line Items]
Goodwill impairment		$ 719	$ 0	$ 25
Amortization of intangible assets		71	$ 65	67
Engineered Products and Solutions
Goodwill [Line Items]
Goodwill impairment	$ 719	719
Transportation and Construction Solutions
Goodwill [Line Items]
Goodwill impairment				$ 25
Minimum
Goodwill [Line Items]
Expected amortization for the year 2018	60	60
Expected amortization for the year 2019	60	60
Expected amortization for the year 2020	60	60
Expected amortization for the year 2021	60	60
Expected amortization for the year 2022	60	60
Maximum
Goodwill [Line Items]
Expected amortization for the year 2018	75	75
Expected amortization for the year 2019	75	75
Expected amortization for the year 2020	75	75
Expected amortization for the year 2021	75	75
Expected amortization for the year 2022	$ 75	$ 75