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Employee Benefit Plans - Individually Significant (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Multiemployer Plans [Line Items]
Company Contributions	$ 54	$ 52	$ 47
Multiemployer Plan, Total Individually Significant Pension Plans [Member]
Multiemployer Plans [Line Items]
Company Contributions	39	38	35
Automotive Industries Pension Plan [Member]
Multiemployer Plans [Line Items]
Company Contributions	1	1	1
Midwest Operating Engineers Pension Trust Fund [Member]
Multiemployer Plans [Line Items]
Company Contributions	2	2	2
Suburban Teamsters of Northern Illinois Pension Plan [Member]
Multiemployer Plans [Line Items]
Company Contributions	3	3	3
Western Conference of Teamsters Pension Plan [Member]
Multiemployer Plans [Line Items]
Company Contributions	33	32	29
Multiemployer Plan, Aggregate Individually Insignificant Pension Plans [Member]
Multiemployer Plans [Line Items]
Company Contributions	$ 15	$ 14	$ 12

X

- Definition

Amount of cost for employer contribution to multiemployer pension plan determined to be individually significant.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

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- Definition

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+ References

No definition available.

+ Details

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