Multiemployer Plans Participation by Plan (Details 19) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Multiemployer Plans [Line Items]
Entity tax ID number	30-1133956
Pension Benefits
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Insignificant, Employer Contribution, Cost	$ 30,931	$ 24,512	$ 21,421
Multiemployer Plan, Employer Contribution, Cost	$ 85,444	$ 72,525	58,722
Alaska Laborers-Employers Retirement Fund \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	91-6028298
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Jun. 30, 2020	Jun. 30, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 828	$ 815	732
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Dec. 31, 2020
Construction Industry and Laborers Joint Pension Trust for So Nevada, Plan A \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	88-0135695
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 515	$ 544	346
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jun. 30, 2023
Edison Pension Plan \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	93-6061681
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 16,121	$ 12,252	12,111
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Dec. 31, 2021
IBEW Local 212 Pension Trust \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	31-6127280
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Apr. 30, 2020	Apr. 30, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 1,521	$ 1,110	1,341
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jun. 01, 2025
IBEW Local 357 Pension Plan A \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	88-6023284
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 9,913	$ 10,162	3,460
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	May 31, 2021
IBEW Local 38 Pension Plan \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	34-6574238
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Red	Yellow
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Apr. 30, 2020	Apr. 30, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 140	$ 158	116
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Apr. 23, 2023
IBEW Local 648 Pension Plan \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	31-6134845
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Feb. 28, 2020	Feb. 28, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 526	$ 728	2,175
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Aug. 29, 2021
IBEW Local 82 Pension Plan \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	31-6127268
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Jun. 30, 2020	Jun. 30, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 1,373	$ 1,662	1,569
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Dec. 03, 2023
Idaho Plumbers and Pipefitters Pension Plan \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	82-6010346
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	May 31, 2020	May 31, 2019
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 1,370	$ 1,307	1,247
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Mar. 31, 2023
Minnesota Teamsters Construction Division Pension Fund \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	41-6187751
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Certified Zone Status, Date	Nov. 30, 2019	Nov. 30, 2018
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 663	$ 673	740
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Apr. 30, 2021
National Automatic Sprinkler Industry Pension Fund \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	52-6054620
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 954	$ 1,074	738
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
National Automatic Sprinkler Industry Pension Fund \| Pension Benefits \| Minimum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Mar. 31, 2021
National Automatic Sprinkler Industry Pension Fund \| Pension Benefits \| Maximum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jul. 31, 2024
National Electrical Benefit Fund \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	53-0181657
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Green	Green
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	No
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 14,484	$ 12,679	8,468
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
National Electrical Benefit Fund \| Pension Benefits \| Minimum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Dec. 31, 2021
National Electrical Benefit Fund \| Pension Benefits \| Maximum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Aug. 30, 2025
Pension Trust Fund for Operating Engineers \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	94-6090764
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 2,680	$ 2,598	2,403
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Pension Trust Fund for Operating Engineers \| Pension Benefits \| Minimum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jun. 15, 2022
Pension Trust Fund for Operating Engineers \| Pension Benefits \| Maximum
Multiemployer Plans [Line Items]
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jun. 30, 2023
Sheet Metal Workers Pension Plan of Southern CA, AZ, and NV \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	95-6052257
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Yellow	Yellow
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 3,255	$ 2,119	1,774
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jun. 30, 2024
Southwest Marine Pension Trust \| Pension Benefits
Multiemployer Plans [Line Items]
Entity tax ID number	95-6123404
Multiemployer Plan, Pension, Significant, Plan Number	001
Multiemployer Plan, Pension, Significant, Certified Zone Status [Fixed List]	Red	Red
Multiemployer Plan, Pension, Significant, Funding Improvement or Rehabilitation Plan, Implementation Status [Fixed List]	Implemented
Multiemployer Plan, Pension, Significant, Employer Contribution, Cost	$ 170	$ 132	$ 81
Multiemployer Plan, Pension, Significant, Surcharge [Fixed List]	No
Multiemployer Plan, Pension, Significant, Collective-Bargaining Arrangement, Expiration Date	Jan. 31, 2024

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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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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Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

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Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

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