Equity-Based Compensation - RSUs to be Settled in Cash (Detail) - Restricted Stock Units to be Settled in Cash - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | |||
|---|---|---|---|---|---|
Jun. 30, 2018 |
Jun. 30, 2017 |
Jun. 30, 2018 |
Jun. 30, 2017 |
Dec. 31, 2017 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Amount in cash received for each RSU is equal to the fair value of this number of Quanta common stock shares (in shares). | 1 | ||||
| Compensation expense related to RSUs to be settled in cash | $ 1.5 | $ 1.2 | $ 2.8 | $ 3.9 | |
| Payments to settle liabilities under compensation plan | 3.8 | $ 3.8 | 6.0 | $ 6.1 | |
| Accrued liabilities under compensation plan | $ 1.4 | $ 1.4 | $ 4.6 | ||
| Minimum | |||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Vesting period for RSUs to be settled in cash | 2 years | ||||
| Maximum | |||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | |||||
| Vesting period for RSUs to be settled in cash | 3 years | ||||
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- Definition Amount in cash received for each RSU is equal to the fair value of this number of Quanta common stock shares. No definition available.
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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate carrying value as of the balance sheet date of the liabilities for stock option plans and other equity-based compensation arrangements payable within one year (or the operating cycle, if longer). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. No definition available.
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