Adoption of New Accounting Standards (Details) (USD $)
In Millions, unless otherwise specified
Oct. 31, 2011
Adoption Of New Accounting Standards Disclosure Details [Abstract]  
Nonconsolidated CLO entity with non-recourse assets $ 487.0
Nonconsolidated CLO entity with non-recourse liabilities 456.3
Maximum exposure to loss on VIE direct investment and beneficial interest 2.3
Maximum exposure to loss on VIE investment management fees receivable $ 0.5