XML 99 R74.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Employee Benefit Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011
Employee Benefit Plans [Line Items] |  |  |
Partial withdrawal liability |  |  | $ 32.6
Multiemployer defined contribution and other benefit plan contributions other than MEP DBP | 104.4 | 87.0 | 46.7
401K Plan [Member] |  |  |
Employee Benefit Plans [Line Items] |  |  |
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 three and six percent | 50.00% |  |
Percentage of employee contribution, lower range | 3.00% |  |
Percentage of employee contribution, high range | 6.00% |  |
Quanta 401(k) Plan, Contributions to non-union defined contribution plans | $ 11.8 | $ 11.0 | $ 9.5
Red Zone [Member] |  |  |
Employee Benefit Plans [Line Items] |  |  |
Percentage Funded in this Zone | Less than 65% |  |
Yellow Zone [Member] |  |  |
Employee Benefit Plans [Line Items] |  |  |
Percentage Funded in this Zone | Less than 80% |  |
Green Zone [Member] |  |  |
Employee Benefit Plans [Line Items] |  |  |
Percentage Funded in this Zone | at least 80% |  |

X
- Details
Name: | pwr_EmployeeBenefitPlansLineItems
Namespace Prefix: | pwr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Multiemployer defined contribution plan period contributions. + References No definition available. + Details
Name: | pwr_MultiemployerDefinedContributionPlanPeriodContributions
Namespace Prefix: | pwr_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Percentage Funded In This Zone + References No definition available. + Details
Name: | pwr_PercentageFundedInThisZone
Namespace Prefix: | pwr_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of contribution by employer of each employee contribution up to specific percentage. + References No definition available. + Details
Name: | pwr_PercentageOfContributionByEmployerOfEachEmployeeContributionUpToSpecificPercentage
Namespace Prefix: | pwr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of contribution by employer of each employee who contributes between three and six percent. + References No definition available. + Details
Name: | pwr_PercentageOfContributionByEmployerOfEachEmployeeWhoContributesToPlan
Namespace Prefix: | pwr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of employee contribution, high range. + References No definition available. + Details
Name: | pwr_PercentageOfEmployeeContributionHighRange
Namespace Prefix: | pwr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of employee contribution, low range. + References No definition available. + Details
Name: | pwr_PercentageOfEmployeeContributionLowRange
Namespace Prefix: | pwr_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
Name: | us-gaap_DefinedContributionPlanCostRecognized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of the obligation recognized by withdrawing from 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. + References No definition available. + Details
Name: | us-gaap_MultiemployerPlansWithdrawalObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant