Maximum value of common stock purchased during period.

No definition available.

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- Definition

Amount of cost for defined contribution plan.

+ References

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-Topic 715
-SubTopic 70
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- Definition

Amount of expense for employee benefit and equity-based compensation.

+ References

No definition available.

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- Definition

Amount of contribution received by multiemployer pension plan from all employers participating in multiemployer pension plan determined to be individually significant.

+ References

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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.

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Balance Type:	na
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- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

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-Topic 718
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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

+ References

No definition available.

+ Details

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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Employee Benefit Plans - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Multiemployer Plans [Line Items]
Number of common stock issued related to ESPP	411,320		411,320
ESPP [Member]
Multiemployer Plans [Line Items]
Share-based compensation arrangement by share-based payment award, purchase price of common stock, percent			85.00%
Maximum number of shares purchased in offering period			500
Maximum value of common stock purchased during period under ESPP			$ 10,000,000,000
Expense related to ESPP	$ 1,000,000		3,000,000
Multiemployer Pension And Other Multiemployer Benefit Plans And Trusts [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan Contributions	26,000,000	$ 25,000,000	69,000,000	$ 71,000,000
Profit Sharing Plan [Member]
Multiemployer Plans [Line Items]
Expense recognized	$ 4,000,000		$ 11,000,000	$ 6,000,000
Profit Sharing Plan [Member] \| Maximum [Member]
Multiemployer Plans [Line Items]
Expense recognized		$ 1,000,000