Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Outstanding Capital Commitments Associated with Investments in Unconsolidated Affiliates (Parenthetical) (Detail)

v2.4.1.9
Commitments and Contingencies - Outstanding Capital Commitments Associated with Investments in Unconsolidated Affiliates (Parenthetical) (Detail) (Corporate Joint Venture [Member], USD $)
In Millions, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Corporate Joint Venture [Member]
 
Other Commitments [Line Items]  
Return of capital from unconsolidated affiliates anticipated for 2017 $ 44.6pwr_ForecastedReturnsOfCapitalFromUnconsolidatedAffiliatesInTwoYears
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