Non-operating income (expense) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Oct. 31, 2014	Oct. 31, 2013	Oct. 31, 2012
Non-operating income (expense)
Interest and other income	$ 8,182	$ 6,514	$ 7,922
Net gains (losses) on investments and derivatives	(6,946)	(8,154)	10,957
Net foreign currency gains (losses)	(97)	(873)	(462)
Gains and (losses) other investment income, net	1,139us-gaap_OtherNonoperatingIncomeExpense	(2,513)us-gaap_OtherNonoperatingIncomeExpense	18,417us-gaap_OtherNonoperatingIncomeExpense
Interest expense	(29,892)us-gaap_InterestExpense	(33,708)us-gaap_InterestExpense	(33,930)us-gaap_InterestExpense
Loss on extinguishment of debt	0	(52,996)	0
Other income (expense) of consolidated collateralized loan obligation ("CLO") entities:
Interest income	16,174	21,966	22,058
Net gains (losses) on bank loans, other investments and note obligations	(1,282)	(7,151)	22,648
Gains (losses) other investment income, net	14,892	14,815	44,706
Structuring and closing fees	(4,847)	0	0
Interest expense	(10,000)	(19,152)	(18,447)
Interest and other expense	(14,847)ev_CloInterestAndOtherExpenseTotal	(19,152)ev_CloInterestAndOtherExpenseTotal	(18,447)ev_CloInterestAndOtherExpenseTotal
Total non-operating expense	$ (28,708)us-gaap_NonoperatingIncomeExpense	$ (93,554)us-gaap_NonoperatingIncomeExpense	$ 10,746us-gaap_NonoperatingIncomeExpense

The total interest and other expenses related to the consolidated CLO entities.

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This item represents the net total realized and unrealized gain (loss) included in earnings for the period on the Company's investment securities and derivatives.

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Net gains (losses) and other investment income of consolidated CLO entity that have been consolidated on the Company's financial statements.

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Interest expense of variable interest entities that have been consolidated on the Company's financial statements.

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Interest income of variable interest entities that have been consolidated on the Company's financial statements.

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Losses on investments and note obligations of variable interest entities that have been consolidated on the Company's financial statements.

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No definition available.

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Discloses the CLO entities nonoperating expense items that could include (a) losses on securities (net of profits) and (b) miscellaneous income deductions.

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No definition available.

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Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

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