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Employee Benefit Plans - Individually Significant (Detail) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Multiemployer Plans [Line Items] |  |  |
Company Contributions | $ 47 | $ 47 | $ 43
Multiemployer Plan, Total Individually Significant Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 41 | 40 | 37
Automotive Industries Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 1 | 1 | 1
Distributors Association Warehousemen's Pension Trust [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 1 | 1 | 1
Local 731 Private Scavengers and Garage Attendants Pension Trust Fund [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 7 | 7 | 7
Suburban Teamsters of Northern Illinois Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 3 | 3 | 2
Teamsters Local 301 Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 1 | 2 | 1
Western Conference of Teamsters Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 27 | 25 | 24
Western Pennsylvania Teamsters and Employers Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | 1 | 1 | 1
Multiemployer Plan, Aggregate Individually Insignificant Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Company Contributions | $ 6 | $ 7 | $ 6

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- 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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