Employee Benefit Plans (Details) - USD ($)	12 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2018
Multiemployer Plans [Line Items]
Contributions to other multiemployer plans	$ 9,172,000	$ 15,019,000	$ 15,152,000
Total contributions made	$ 37,403,000	$ 64,386,000	54,724,000
Boilermaker-Blacksmith National Pension Trust [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	48-6168020/001
Pension Protection Act Zone Status	Yellow	Red
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 6,634,000	$ 12,434,000	8,525,000
Surcharge Imposed	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (1)
Joint Pension Fund Local Union 164 IBEW [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	22-6031199/001
Pension Protection Act Zone Status		Yellow
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 1,560,000	$ 2,180,000	2,391,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2021
Joint Pension Fund Local Union Number 102 IBEW [Member] [Domain]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	22-1615726/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 1,227,000	$ 1,610,000	2,489,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2022
IBEW Local 456 Pension Plan [Member] [Domain]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	22-6238995/001
Pension Protection Act Zone Status		Green
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 427,000	$ 574,000	6,005,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2021
Local 351 IBEW Pension Plan [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	22-3417366/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 1,709,000	$ 2,025,000	1,187,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Dec. 04, 2021
Steamfitters Local Union Number 420 Pension Plan [Member] [Domain]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	23-2004424/001
Pension Protection Act Zone Status	Red	Red
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 1,523,000	$ 639,000	1,558,000
Surcharge Imposed	Yes
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (3)
IBEW Local Union 98 Pension Plan [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	23-1990722/001
Pension Protection Act Zone Status	Red	Red
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 352,000	$ 828,000	1,106,000
Surcharge Imposed	Yes
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (3)
Indiana Laborers Pension Fund [Domain]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	35-6027150/001
Pension Protection Act Zone Status		Green
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 1,604,000	$ 3,349,000	3,542,000
Surcharge Imposed	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (3)
Ironworkers Mid-America Pension Plan, Local 395 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	36-6488227/001
Pension Protection Act Zone Status		Green
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 840,000	$ 2,596,000	4,412,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2024
Pipefitters Retirement Fund, Local 597 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	62-6105084/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 835,000	$ 3,469,000	3,682,000
Surcharge Imposed	No
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (4)
Iron Workers Pension Plan of Western Pennsylvania, Local 3 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	25-1283169/001
Pension Protection Act Zone Status		Yellow
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 500,000	$ 2,317,000	1,539,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 01, 2021
Iron Workers Pension Plan, Loc. 55 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	34-6682351/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 2,951,000	$ 4,333,000	198,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Jun. 30, 2024
National Electrical Benefit Fund, Local 488 and 126 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	53-0181657/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 1,502,000	$ 4,577,000	824,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Jan. 01, 2023
Connecticut Plumbers and Pipefitters Pension Fund, Local 777 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	06-6050353/001
Pension Protection Act Zone Status		Green
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 0	$ 3,307,000	115,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Jun. 01, 2021
Northwestern Ohio Plumbers and Pipe Fitters Local 50 [Member]
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	34-6502487/001
Pension Protection Act Zone Status		Green
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 2,504,000	$ 1,161,000	61,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Mar. 31, 2022
OhioCarpentersPensionFundLocal1090and351
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	34-6574360/001
Pension Protection Act Zone Status	Red	Red
FIP/RP Status Pending or Implemented	Implemented
Multiemployer Plan, Employer Contribution, Cost	$ 3,042,000	$ 2,962,000	318,000
Surcharge Imposed	Yes
Expiration Date of Collective-Bargaining Agreement	Apr. 30, 2021
IBEW Local 654 Pension Plan
Multiemployer Plans [Line Items]
EIN/Pension Plan Number	23-6538183/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)	Described below (2)
FIP/RP Status Pending or Implemented	NA
Multiemployer Plan, Employer Contribution, Cost	$ 1,021,000	$ 1,006,000	$ 1,620,000
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	Jun. 03, 2023

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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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