XML 33 R22.htm IDEA: XBRL DOCUMENT v3.10.0.1
Basis of Presentation and New Accounting Pronouncements - Additional Information (Detail)
Sep. 30, 2018
Jan. 31, 2018
Basis Of Presentation [Line Items]    
Equity method ownership percentage in joint venture 49.00%  
Unnamed Corporate Joint Venture [Member]    
Basis Of Presentation [Line Items]    
Equity method ownership percentage in joint venture 37.50% 49.00%