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Employee Benefit Plans - Individually Significant Information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Multiemployer Plans [Line Items] |  |  |
High end of funded percentage of multiemployer plans in critical status | 65.00% |  |
High end of funded percentage of multiemployer plans in endangered status | 80.00% |  |
Surcharge percentage during first twelve months on contribution rates for plans certified as endangered, seriously endangered or critical | 5.00% |  |
Period for which surcharge is 5% on contribution rates for plans certified as endangered, seriously endangered or critical | 12 months |  |
Accrued benefit liabilities | $ 18 | $ 19 |
Surcharge percentage after first twelve months on contribution rates for plans certified as endangered, seriously endangered or critical | 10.00% |  |
Minimum [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Projected insolvency period | 15 years |  |
Maximum [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Projected insolvency period | 20 years |  |
Suburban Teamsters of Northern Illinois Pension Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Minimum percentage of total contributions provided by the Company relating to multiemployer plans |  | 5.00% | 5.00%
Multiemployer Health and Welfare Plan [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Multiemployer company contributions | $ 48 | $ 45 | $ 43
Withdrawal from Multiemployer Pension Plans [Member] |  |  |
Multiemployer Plans [Line Items] |  |  |
Charge to "Operating" expenses | $ 4 | $ 1 | $ 3

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