XML 58 R47.htm IDEA: XBRL DOCUMENT v3.7.0.1
Former line of credit - Additional Information (Detail) - Letter of Credit - USD ($)
$ in Millions
9 Months Ended
Jul. 31, 2017
Sep. 07, 2016
Line of Credit Facility [Line Items]    
Line of Credit Facility, Expiration Date Sep. 08, 2016  
Line of Credit Facility, Amount Outstanding   $ 5