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Employee Benefit Plans - Summary of Multi-Employer Benefit Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	$ 121,850	$ 102,209	$ 70,420
All other plans
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	17,663	17,117	8,818
Southern California IBEW-NECA Pension Trust Fund | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	32,791	14,268	767
National Electrical Benefit Fund | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	10,850	11,050	9,840
Eighth District Electrical Pension Fund | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	10,998	11,199	9,707
IBEW Local 332 Pension Plan Part A | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	3,418	1,913	0
IBEW Local 769 Management Pension Plan A | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	3,866	2,689	2,587
IBEW Local No. 640 and Arizona NECA Defined Benefit Pension Plan | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	1,195	2,397	1,629
IBEW Local Union 1249 Pension Fund | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	2,126	1,578	881
Indiana/Kentucky/Ohio Regional Council of Carpenters Pension Fund | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	2,109	1,742	1,157
Alaska Electrical Pension Plan | Multiemployer Plans, Pension
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	1,548	1,408	2,723
National Electrical Annuity Plan | Other Postretirement Benefits Plan
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	25,037	28,822	26,559
Eighth District Electrical Pension Fund Annuity Plan | Other Postretirement Benefits Plan
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	4,915	5,339	4,785
San Mateo Country Electrical Construction Industry Retirement Plan | Other Postretirement Benefits Plan
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	3,202	854	0
Puget Sound Electrical Workers 401(K) Savings Plan | Other Postretirement Benefits Plan
Multiemployer Plan, Employer Contribution, Cost [Abstract]
Contributions to Plan	$ 2,132	$ 1,833	$ 967

X

- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=35742348&loc=SL14450788-114948

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 35
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=29639808&loc=d3e29008-114946

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-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 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

+ Details

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- References

No definition available.

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