Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan.

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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.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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-Publisher FASB
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High end of funded percentage of multi employer plans in critical status.

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High end of funded percentage of multi employer plans in endangered status.

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- Definition

Minimum percentage of total contributions provided by the company relating to multi employer plans.

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Period for which surcharge is five percent on contribution rates for plans certified as endangered seriously endangered or critical.

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Projected insolvency period.

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Surcharge percentage after first twelve months on contribution rates for plans certified as endangered seriously endangered or critical.

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Surcharge percentage during first twelve months on contribution rates for plans certified as endangered seriously endangered or critical.

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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