Stock-Based Incentive Compensation Plans and Employee Benefit Plans Multi-employer Plan (Details) - Multiemployer Plans, Pension [Member] $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($)
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 52
Approximate number of unions the Company contributed to on behalf of employees	215
Multiemployer Plans Average Contributions	$ 1
Multiemployer Plans Largest Contribution	$ 5
Number of multiemployer plans contributed to	72
Defined benefit plan, number of significant plans	8
Defined benefit plan, number of plans in red zone status receiving company contributions	4
Defined benefit plan, number of plans whereby company contributions exceed 5% of plan balance	5
Defined benefit plan, percentage threshold by which plan contributions are considered significant	5.00%
Number of plans in red zone status considered significant by the Company	0
Central Pension Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 12
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Indiana Laborers Pension Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 5
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Pipeline Industry Benefit Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 5
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Laborers District Fund of Ohio [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 4
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Ohio Operating Engineers Pension Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 3
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Operating Eng. Local 324 Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 3
Multiemployer Plans, Certified Zone Status [Fixed List]	Red
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	Implemented
Multiemployer Plans, Surcharge [Fixed List]	No
Minnesota Laborers Pension Fund [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 3
Multiemployer Plans, Certified Zone Status [Fixed List]	Green
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	No
Multiemployer Plans, Surcharge [Fixed List]	No
Laborers' Combined Fund of Western Pennsylvania [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 2
Multiemployer Plans, Certified Zone Status [Fixed List]	Red
Multiemployer Plans, Funding Improvement Plan and Rehabilitation Plan [Fixed List]	Implemented
Multiemployer Plans, Surcharge [Fixed List]	No
Other Pension Funds [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 15

The approximate number of unions the Company contributed to during the year on behalf of employees

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Defined benefit plan, number of plans in red zone status receiving company contributions

+ References

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- Definition

Number of plans whereby company contributions exceed 5% of plan balance

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Defined benefit plan, number of significant plans

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Percentage threshold in which plan contributions are considered significant

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- Definition

The average contribution made by the Company to unions within multiemployer plans during the period.

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The largest contribution made by the Company to a single union multiemployer plan during the period.

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No definition available.

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Number of multi-employer plans contributed to

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Number of plans in red zone status considered significant by the Company

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Amount of contributions made to multiemployer plan by employer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 80
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- Definition

Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

+ References

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- Definition

Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA".

+ 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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- Definition

Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA".

+ References

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