Quarterly report pursuant to Section 13 or 15(d)

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

v3.7.0.1
Commitments and Contingencies - Outstanding Capital Commitments Associated with Investments in Unconsolidated Affiliates (Detail) - Corporate Joint Venture - Other Commitments, Engineering, Procurement and Construction Electric Transmission Project
$ in Thousands
Jun. 30, 2017
USD ($)
Other Commitments [Line Items]  
Capital commitments, Remainder of 2017 $ 34,953
Capital commitments, 2018 0
Capital commitments, 2019 24,444
Total capital commitments associated with investments in an unconsolidated affiliate related to an EPC electrical transmission project $ 59,397