Revenue from Contracts with Customers - Schedule of Revenue, Remaining Performance Obligations (Details) $ in Thousands	Sep. 30, 2023 USD ($)
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 8,635,443
Remaining performance obligations, percent	100.00%
UNITED STATES
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 8,481,328
Remaining performance obligations, percent	98.00%
UNITED STATES \| United States Electrical Construction And Facilities Services [Member]
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 2,158,104
Remaining performance obligations, percent	25.00%
UNITED STATES \| United States Mechanical Construction And Facilities Services [Member]
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 4,875,551
Remaining performance obligations, percent	56.00%
UNITED STATES \| United States Building Services [Member]
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 1,313,779
Remaining performance obligations, percent	15.00%
UNITED STATES \| United States Industrial Services [Member]
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 133,894
Remaining performance obligations, percent	2.00%
UNITED KINGDOM \| United Kingdom Building Services [Member] [Member]
Schedule of Remaining Performance Obligations [Line Items]
Remaining performance obligations	$ 154,115
Remaining performance obligations, percent	2.00%

[Line Items] for Schedule of Remaining Performance Obligations [Table]

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Amount of transaction price allocated to performance obligation that has not been recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (a)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

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- Definition

Percentage of remaining performance obligation to total remaining performance obligation not recognized as revenue.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)(1)
-SubTopic 10
-Topic 606
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-13

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