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Employee Benefit Plans - Individually Significant (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Multiemployer Plans [Line Items]
Company Contributions	$ 47	$ 47	$ 47
Multiemployer Plan, Total Individually Significant Pension Plans [Member]
Multiemployer Plans [Line Items]
Company Contributions	33	32	30
Automotive Industries Pension Plan [Member]
Multiemployer Plans [Line Items]
Company Contributions	1	1	1
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	29	27	25
Western Pennsylvania Teamsters and Employers Pension Plan [Member]
Multiemployer Plans [Line Items]
Company Contributions		1	1
Multiemployer Plan, Aggregate Individually Insignificant Pension Plans [Member]
Multiemployer Plans [Line Items]
Company Contributions	$ 14	$ 15	$ 17

X

- Definition

Amount of contributions made to multiemployer plan by employer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-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 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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