Acquisitions - Aggregate Consideration Paid or Payable and Allocation of Net Assets (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023
Business Acquisition [Line Items]
Goodwill	$ 4,283,804	$ 4,045,905
Acquisitions 2024
Business Acquisition [Line Items]
Cash paid or payable	382,929
Value of Quanta common stock issued	51,768
Contingent consideration	14,463
Fair value of total consideration transferred or estimated to be transferred	449,160
Cash and cash equivalents	8,453
Accounts receivable	50,845
Contract assets	162
Inventories	14,127
Prepaid expenses and other current assets	12,176
Property and equipment	92,676
Operating lease right-of-use assets	15,532
Other assets	456
Identifiable intangible assets	122,301
Current maturities of long-term debt	(4,431)
Current portion of operating lease liabilities	(4,134)
Accounts payable and accrued liabilities	(51,325)
Contract liabilities	(390)
Long-term debt, net of current maturities	(4,436)
Operating lease liabilities, net of current portion	(11,398)
Deferred income taxes	(42,363)
Total identifiable net assets	198,251
Goodwill	250,909
Fair value of net assets acquired	$ 449,160