Contingencies and Commitments - Changes in Carrying Value of Recorded Environmental Remediation Reserves (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2019	Dec. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Beginning balance	$ 280	$ 294
Cash payments	(3)	(25)
Liabilities incurred	1	19
Reversals of previously recorded liabilities	(1)	(3)
Foreign currency translation and other	(1)	(5)
Ending balance	$ 276	$ 280

Accrual for environmental loss contingencies foreign currency translation gain loss and other.

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- Definition

Total costs accrued as of the balance sheet date for environmental loss contingencies.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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- Definition

Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of expense (reversal of expense) which increases (decreases) the accrual for environmental loss contingencies from revisions in estimates to existing obligations. Excludes changes related to business acquisitions, divestitures, or currency movement.

+ References

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- Definition

Amount of cash outflow to settle environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section S99
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