DERIVATIVE FINANCIAL INSTRUMENTS, Balance Sheet Location (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Sep. 30, 2014
Forward foreign exchange contracts
Derivative assets [Abstract]
Fair value	$ 8,000	$ 2,462
Interest rate contract
Derivative assets [Abstract]
Fair value	121,414
Designated as hedging instrument \| Forward foreign exchange contracts \| Prepaid expenses and other assets
Derivative assets [Abstract]
Notional amount	553,766	609,018
Fair value	6,794	2,101
Designated as hedging instrument \| Interest rate contract
Liabilities derviatives [Abstract]
Fair value	2,481
Designated as hedging instrument \| Interest rate contract \| Other liabilities
Liabilities derviatives [Abstract]
Notional amount	200,000	0
Fair value	2,481	0
Derivatives not designated as hedging instruments \| Forward foreign exchange contracts \| Prepaid expenses and other assets
Derivative assets [Abstract]
Notional amount	98,531	105,179
Fair value	1,206	361
Derivatives not designated as hedging instruments \| Interest rate contract
Derivative assets [Abstract]
Fair value		89,923
Liabilities derviatives [Abstract]
Fair value	105,050	75,668
Derivatives not designated as hedging instruments \| Interest rate contract \| Trading instruments
Derivative assets [Abstract]
Notional amount	2,510,991	2,198,357
Fair value	121,414	89,923
Derivatives not designated as hedging instruments \| Interest rate contract \| Derivative instruments associated with offsetting matched book positions
Derivative assets [Abstract]
Notional amount	1,766,733	1,796,288
Fair value	421,850	323,337
Liabilities derviatives [Abstract]
Notional amount	1,766,733	1,796,288
Fair value	421,850	323,337
Derivatives not designated as hedging instruments \| Interest rate contract \| Trading instruments sold
Liabilities derviatives [Abstract]
Notional amount	2,497,071	2,185,085
Fair value	$ 105,050	$ 75,668

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and elected not to be offset.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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- Definition

Nominal or face amount used to calculate payments on the derivative asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5579245-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6519104

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

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Nominal or face amount used to calculate payments on the derivative liability.

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