Employee Benefit Plans - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percent of employees covered by collective bargaining agreements	34.00%
Contributions	$ 167,399	$ 132,996	$ 121,978
Percentage of contribution by employer of each employee's contribution up to 3%	100.00%
Percentage of contribution by employer of each employee who contributes between 3% and 6%	50.00%
Contributions to Quanta 401(k) Plan	$ 61,700	50,700	45,900
Contributions to the deferred compensation plans	1,500	1,400	1,300
Discretionary contributions	0	0	0
Deferred compensation obligations included in other long-term liabilities	67,400	74,200
Investments in company-owned life insurance policies	64,000	73,800
Increase (decrease) to fair market value of plan liabilities	13,192	(10,428)	(7,507)
Increase (decrease) to fair market value of plan assets	$ (13,757)	8,566	6,857
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of employee contribution, lower range	3.00%
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of employee contribution, lower range	6.00%
Multiemployer Defined Contribution and Other Benefit Plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Contributions	$ 234,300	$ 213,400	$ 188,600

Defined Contribution Plan, Employer Matching Contribution, Percent of Match By Employer Up To Specific Percentage

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Defined Contribution Plan, Employer Matching Contribution, Percent of Match By Employer Of Each Employee Who Contributes To Plan

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Amount of contributions made by employer into fund established for purposes of making future disbursement to individual in accordance with deferred compensation arrangement.

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of cost for defined contribution plan.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan.

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The increase (decrease) during the reporting period in the obligation created by employee agreements whereby earned compensation will be paid in the future.

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This item represents the amount that could be realized under a life insurance contract or contracts owned by the Entity as of the date of the statement of financial position. Such Entity-owned life insurance policies are commonly known as corporate-owned life insurance (COLI) or bank-owned life insurance (BOLI).

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The change in cash surrender or contract value during the period which adjusted the amount of premiums paid in determining the expense or income recognized under the contract for the period.

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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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Percentage of entity's employees covered by collective-bargaining arrangement (CBA) to all participants in multiemployer pension plan determined to be individually significant.

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