Multiemployer Plans (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Multiemployer Plans [Line Items]
Entity tax ID number	30-1133956
Multiemployer Plans, Pension [Member]
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 72,525	$ 58,722	$ 56,745
Multiemployer Plans, Pension [Member] \| Alaska Laborers-Employers Retirement Fund
Multiemployer Plans [Line Items]
Entity tax ID number	91-6028298
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plans, Certified Zone Status, Date	Jun. 30, 2019	Jun. 30, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 815	$ 732	690
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Dec. 31, 2020
Multiemployer Plans, Pension [Member] \| Construction Industry and Laborers Joint Pension Trust for So Nevada, Plan A
Multiemployer Plans [Line Items]
Entity tax ID number	88-0135695
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 544	$ 346	377
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Jun. 30, 2020
Multiemployer Plans, Pension [Member] \| Edison Pension Plan
Multiemployer Plans [Line Items]
Entity tax ID number	93-6061681
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 12,252	$ 12,111	12,725
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Dec. 31, 2020
Multiemployer Plans, Pension [Member] \| IBEW Local 212 Pension Trust
Multiemployer Plans [Line Items]
Entity tax ID number	31-6127280
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Apr. 30, 2019	Apr. 30, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 1,110	$ 1,341	1,312
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Jun. 01, 2025
Multiemployer Plans, Pension [Member] \| IBEW Local 357 Pension Plan A
Multiemployer Plans [Line Items]
Entity tax ID number	88-6023284
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 10,162	$ 3,460	3,286
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	May 31, 2021
Multiemployer Plans, Pension [Member] \| IBEW Local 648 Pension Plan
Multiemployer Plans [Line Items]
Entity tax ID number	31-6134845
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plans, Certified Zone Status, Date	Feb. 28, 2019	Feb. 28, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 728	$ 2,175	2,254
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Aug. 29, 2021
Multiemployer Plans, Pension [Member] \| IBEW Local 82 Pension Plan
Multiemployer Plans [Line Items]
Entity tax ID number	31-6127268
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Jun. 30, 2019	Jun. 30, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 1,662	$ 1,569	1,757
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Dec. 03, 2023
Multiemployer Plans, Pension [Member] \| Idaho Plumbers and Pipefitters Pension Plan
Multiemployer Plans [Line Items]
Entity tax ID number	82-6010346
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	May 31, 2019	May 31, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 1,307	$ 1,247	1,156
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Mar. 31, 2023
Multiemployer Plans, Pension [Member] \| Minnesota Teamsters Construction Division Pension Fund
Multiemployer Plans [Line Items]
Entity tax ID number	41-6187751
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Nov. 30, 2018	Nov. 30, 2017
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 673	$ 740	826
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Apr. 30, 2021
Multiemployer Plans, Pension [Member] \| National Automatic Sprinkler Industry Pension Fund
Multiemployer Plans [Line Items]
Entity tax ID number	52-6054620
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 1,074	$ 738	718
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, First	Mar. 31, 2021
Expiration Date of Collective Bargaining Agreement	Jul. 31, 2024
Multiemployer Plans, Pension [Member] \| National Electrical Benefit Fund
Multiemployer Plans [Line Items]
Entity tax ID number	53-0181657
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	No
Multiemployer Plan, Contributions by Employer	$ 12,679	$ 8,468	8,891
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, First	Aug. 31, 2019
Expiration Date of Collective Bargaining Agreement	Jun. 01, 2025
Multiemployer Plans, Pension [Member] \| Pension Trust Fund for Operating Engineers
Multiemployer Plans [Line Items]
Entity tax ID number	94-6090764
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 2,598	$ 2,403	2,391
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, First	Mar. 31, 2020
Expiration Date of Collective Bargaining Agreement	Jun. 15, 2022
Multiemployer Plans, Pension [Member] \| Sheet Metal Workers Pension Plan of Southern CA, AZ, and NV
Multiemployer Plans [Line Items]
Entity tax ID number	95-6052257
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 2,119	$ 1,774	1,016
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Jun. 30, 2020
Multiemployer Plans, Pension [Member] \| Southwest Marine Pension Trust
Multiemployer Plans [Line Items]
Entity tax ID number	95-6123404
Multiemployer Plan Number	001
Multiemployer Plans, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plans, Certified Zone Status, Date	Dec. 31, 2019	Dec. 31, 2018
FIP/RP Status Pending/Implemented	Implemented
Multiemployer Plan, Contributions by Employer	$ 132	$ 81	48
Multiemployer Plans, Surcharge [Fixed List]	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date	Jan. 31, 2024
Multiemployer Plans, Pension [Member] \| Other funds
Multiemployer Plans [Line Items]
Multiemployer Plan, Contributions by Employer	$ 24,670	$ 21,537	$ 19,298
Minimum
Multiemployer Plans [Line Items]
Multiemployer plan yellow zone status funded percentage	65.00%
Multiemployer plan green zone status funded percentage	80.00%
Maximum
Multiemployer Plans [Line Items]
Multiemployer plan red zone status funded percentage	65.00%
Mulitiemployer plan yellow status funded percentage	80.00%

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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Mulitiemployer plan yellow status funded percentage

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Multiemployer plan green zone status funded percentage

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Multiemployer plan red zone status funded percentage

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Amount of contributions made to multiemployer plan by employer.

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Three digit plan number 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.

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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.

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Date of the multiemployer plan's year end to which the certified zone status relates, in CCYY-MM-DD format. 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.

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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan, in CCYY-MM-DD format. 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.

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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire first in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. 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.

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Expiration date of the collective bargaining arrangement requiring contributions to the multiemployer plan that will expire last in a group of associated collective bargaining arrangements, in CCYY-MM-DD format. 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.

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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".

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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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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".

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