DERIVATIVE FINANCIAL INSTRUMENTS, Income Statement Location (Details) (Interest rate contracts [Member], Derivatives not designated as hedging instruments [Member], USD $) In Thousands	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Net trading profits [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on derivatives recognized in Income	$ 750	$ (3,471)	$ (505)
Other revenues [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain (loss) on derivatives recognized in Income	$ 0	$ (297)	$ (1,004)