Derivative Instruments (Details 2) (Interest Rate Contracts, USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2014 Fair Value Hedges	Oct. 31, 2013 Fair Value Hedges	Jul. 31, 2013 Fair Value Hedges
Gain (Loss) on Fair Value Hedges
Gains (losses) on interest rate contracts	$ 31.6	$ (286.8)	$ (49.5)	$ (286.6)
Net accrued interest income on interest rate contracts	41.9	36.1	116.2	111.2
Gains (losses) on borrowings	(33.1)	284.6	47.0	287.0
Accrued interest expense on borrowings	64.3	57.9	179.7	181.5
Fair Value Hedges
Notional amounts					8,254	6,864	6,848
Ineffective portion of the gains (losses) on interest rate fair value hedge derivatives	$ (2.0)	$ (2.0)	$ (3.0)	$ 0.4