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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% |  |

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- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation 12B -Number 240 -Section 12 -Subsection b-2 + Details
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- Definition Mulitiemployer plan yellow status funded percentage + References No definition available. + Details
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- Definition 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 -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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