Derivative Financial (Other Derivative Financial Instruments Not Designated for Hedge Accounting (Details) $ in Thousands	12 Months Ended
	Oct. 31, 2019 USD ($) Number	Oct. 31, 2018 USD ($) Number	Oct. 31, 2017 USD ($)
Derivative [Line Items]
Total other assets fair value	$ 2,074	$ 6,347
Total other liabilities fair value	3,314	4,446
Net gains (losses)	$ (15,913)	$ 984	$ (28,973)
Weighted average term of derivative contracts outstanding	6 months 9 days	1 month 21 days
Collateral Pledged [Member]
Derivative [Line Items]
Other assets, restricted cash	$ 7,500	$ 13,100
Credit Default Swap Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	1	1
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 8,000	$ 5,000
Total other assets fair value	360	0
Total other liabilities fair value	0	10
Net gains (losses)	$ (251)	$ 178	0
Total Return Swap Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	2	3
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 84,000	$ 106,500
Total other assets fair value	396	0
Total other liabilities fair value	114	3,297
Net gains (losses)	$ (5,535)	$ (2,708)	(3,569)
Stock Index Futures Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	1,370	1,007
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 108,300	$ 91,500
Total other assets fair value	615	5,055
Total other liabilities fair value	1,841	372
Net gains (losses)	$ (6,701)	$ 4,267	(23,905)
Commodity Futures Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	415	253
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 15,200	$ 11,600
Total other assets fair value	319	770
Total other liabilities fair value	334	216
Net gains (losses)	$ 531	$ (1,044)	(574)
Foreign Exchange Contract [Member]
Derivative [Line Items]
Number of contracts | Number	26	28
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 56,400	$ 23,000
Total other assets fair value	51	329
Total other liabilities fair value	615	202
Net gains (losses)	$ (1,749)	$ (51)	(595)
Currency Futures Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	231	165
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 24,000	$ 16,900
Total other assets fair value	128	14
Total other liabilities fair value	153	332
Net gains (losses)	$ 442	$ (24)	0
Interest Rate Futures Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	151	282
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 22,300	$ 48,000
Total other assets fair value	144	179
Total other liabilities fair value	22	17
Net gains (losses)	$ (2,402)	$ 366	(421)
Interest Rate Swap Contracts [Member]
Derivative [Line Items]
Number of contracts | Number	6	0
Notional amount of other derivative financial instruments not designated for hedge accounting	$ 24,400	$ 0
Total other assets fair value	61	0
Total other liabilities fair value	235	0
Net gains (losses)	$ (248)	$ 0	$ 91