Employee Benefit Plans (Details) - USD ($)	12 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017
Multiemployer Pension Plans
Total contributions made	$ 64,386	$ 54,724	$ 48,709
Contributions to other multiemployer plans	$ 20,148	$ 17,151	19,514
Boilermaker-Blacksmith National Pension Trust [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (1)
Multiemployer Pension Plans
EIN/Pension Plan Number	48-6168020/001
Pension Protection Act Zone Status	Red	Yellow
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 12,434	$ 8,525	7,098
Multiemployer Plan, Surcharge	Yes
Joint Pension Fund Local Union 164 IBEW [Member]
Multiemployer Pension Plans
EIN/Pension Plan Number	22-6031199/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
Pension Protection Act Zone Status		Yellow
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 2,180	$ 2,391	2,709
Multiemployer Plan, Surcharge	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2021
Joint Pension Fund Local Union Number 102 IBEW [Member] [Domain]
Multiemployer Pension Plans
EIN/Pension Plan Number	22-1615726/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 1,610	$ 2,489	2,392
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2022
IBEW Local 456 Pension Plan [Member] [Domain]
Multiemployer Pension Plans
EIN/Pension Plan Number	22-6238995/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 574	$ 6,005	2,777
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2021
Local 351 IBEW Pension Plan [Member]
Multiemployer Pension Plans
EIN/Pension Plan Number	22-3417366/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 2,025	$ 1,187	2,796
Multiemployer Plan, Surcharge	No
Expiration Date of Collective-Bargaining Agreement	Dec. 04, 2021
Steamfitters Local Union Number 420 Pension Plan [Member] [Domain]
Multiemployer Pension Plans
EIN/Pension Plan Number	23-2004424/001
Pension Protection Act Zone Status	Red	Red
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 639	$ 1,558	2,234
Surcharge Imposed	Yes
Expiration Date of Collective-Bargaining Agreement	Apr. 30, 2020
IBEW Local Union 98 Pension Plan [Member]
Multiemployer Pension Plans
EIN/Pension Plan Number	23-1990722/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
Pension Protection Act Zone Status		Red
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 828	$ 1,106	1,519
Multiemployer Plan, Surcharge	Yes
Expiration Date of Collective-Bargaining Agreement	May 29, 2020
Indiana Laborers Pension Fund [Domain]
Multiemployer Pension Plans
EIN/Pension Plan Number	35-6027150/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
Pension Protection Act Zone Status		Yellow
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 3,349	$ 3,542	2,458
Multiemployer Plan, Surcharge	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2020
Ironworkers Mid-America Pension Plan, Local 395 [Member]
Multiemployer Pension Plans
EIN/Pension Plan Number	36-6488227/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 2,596	$ 4,412	1,785
Surcharge Imposed	No
Expiration Date of Collective-Bargaining Agreement	May 31, 2024
Pipefitters Retirement Fund, Local 597 [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	Described below (3)
Multiemployer Pension Plans
EIN/Pension Plan Number	62-6105084/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 3,469	$ 3,682	2,563
Surcharge Imposed	No
Iron Workers Pension Plan of Western Pennsylvania, Local 3 [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	5/1/2021
Multiemployer Pension Plans
EIN/Pension Plan Number	25-1283169/001
Pension Protection Act Zone Status	Yellow	Yellow
FIP/RP Status Pending or Implemented	Implemented
Total contributions made	$ 2,317	$ 1,539	748
Surcharge Imposed	No
Iron Workers Pension Plan, Loc. 55 [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	6/30/2020
Multiemployer Pension Plans
EIN/Pension Plan Number	34-6682351/001
Multiemployer Plans, Certified Zone Status, Description	Described below (2)
Pension Protection Act Zone Status		Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 4,333	$ 198	0
Surcharge Imposed	No
National Electrical Benefit Fund, Local 488 [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	1/1/2023
Multiemployer Pension Plans
EIN/Pension Plan Number	53-0181657/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 4,577	$ 824	116
Surcharge Imposed	No
Connecticut Plumbers and Pipefitters Pension Fund, Local 777 [Member]
Multiemployer Plans [Line Items]
Multiemployer Plans, Collective-Bargaining Arrangement, Expiration Date, Description	6/1/2020
Multiemployer Pension Plans
EIN/Pension Plan Number	06-6050353/001
Pension Protection Act Zone Status	Green	Green
FIP/RP Status Pending or Implemented	NA
Total contributions made	$ 3,307	$ 115	$ 0
Surcharge Imposed	No

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Multiemployer plans number.

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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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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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