XML 81 R64.htm IDEA: XBRL DOCUMENT v3.8.0.1
Revenues from Contracts with Customers - Additional Information (Detail) - Advisory Fees [Member]
Mar. 31, 2018
USD ($)
Revenue from Contracts with Customers [Line Items]  
Contract assets $ 0
Contract liabilities 0
Costs incurred to obtain or fulfill contracts with customers $ 0