Contingencies - Changes in Carrying Value of Recorded Environmental Remediation Reserves (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Commitments And Contingencies Disclosure [Abstract]
Beginning balance			$ 322	$ 335	$ 335
Liabilities incurred			4	2	7
Cash payments	$ (6)	$ (6)	(11)	$ (9)	(19)
Reversals of previously recorded liabilities	(10)		(17)
Foreign currency translation and other					(1)
Ending balance	$ 298		$ 298		$ 322

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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-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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Amount of expense for newly incurred environmental loss contingencies. Includes, but is not limited to, remediation expense and interest accretion.

+ References

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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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Amount of cash outflow to settle environmental loss contingencies.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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