LONG-TERM DEBT (Schedule of Convertible Notes) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Debt Instrument [Line Items]
Principal amount of convertible notes	$ 467	$ 505
Unamortized discount on convertible notes	(52)	(66)
Net carrying value	415	439
Repurchase of convertible notes	31	24	0
Convertible Notes [Member]
Debt Instrument [Line Items]
Unamortized discount on convertible notes	(31)
Contractual interest coupon	30	29	22
Amortization of debt discount	9	8	10
Repurchase of convertible notes	5	5	0
Total	$ 44	$ 42	$ 32

The amount of contractual interest coup for the period.

No definition available.

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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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Carrying value as of the balance sheet date of long-term debt (with maturities initially due after one year or beyond the operating cycle if longer) identified as Convertible Notes Payable, excluding current portion. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of a written promise to pay a note, initially due after one year or beyond the operating cycle if longer, which can be exchanged for a specified amount of one or more securities (typically common stock), at the option of the issuer or the holder.

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The amount of debt discount that was originally recognized at the issuance of the instrument that has yet to be amortized.

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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 for debt.

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