Quarterly report pursuant to Section 13 or 15(d)

Summary of Significant Accounting Policies - Investments in Affiliates and Other Entities (Detail)

v3.10.0.1
Summary of Significant Accounting Policies - Investments in Affiliates and Other Entities (Detail) - Capital for infrastructure projects
$ in Millions
Jun. 30, 2018
USD ($)
Summary Of Significant Accounting Policies [Line Items]  
Other commitment $ 80.0
Infrastructure investors partnership  
Summary Of Significant Accounting Policies [Line Items]  
Other commitment $ 1,000.0