Non-operating Income (Expense) (Tables)
6 Months Ended
Apr. 30, 2017
Non Operating Income (Expense) Table [Abstract]  
Summary of non-operating income (expense)
   Three Months EndedSix Months Ended
   April 30, April 30,
 (in thousands) 2017 2016 2017 2016
 Interest and other income$ 5,958$ 4,186$ 10,601$ 5,361
 Net gains (losses) on investments and derivatives   3,483  789  (453)  1,374
 Net foreign currency losses  (153)  (1,186)  (366)  (106)
 Gains and other investment income, net  9,288  3,789  9,782  6,629
 Interest expense  (8,065)  (7,340)  (15,412)  (14,682)
 Other income (expense) of consolidated CLO entity:        
   Interest income  -  4,850  -  8,593
   Net gains on bank loans, other investments and         
   note obligations  -  9,058  -  8,594
   Gains and other investment income, net  -  13,908  -  17,187
   Interest expense  -  (2,878)  -  (4,714)
 Total non-operating income (expense)$ 1,223$ 7,479$ (5,630)$ 4,420