Carrying value as of the balance sheet date of the sum of short-term debt and current maturities of long-term debt and capital lease obligations, which are due within one year (or one business cycle if longer).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 19
-Article 5

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The stated principal amount of the debt instrument at time of issuance, which may vary from the carrying amount because of unamortized premium or discount.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
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Interest rate stated in the contractual debt agreement.

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-Name Regulation S-X (SX)
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
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-Paragraph 16, 20

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The cash outflow for the extinguishment of borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
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Amount represents the difference between the fair value of the payments made and the carrying amount of the debt at the time of its extinguishment.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher AICPA
-Name Accounting Principles Board Opinion (APB)
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Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

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-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 2, 4

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Including current and noncurrent portions, aggregate carrying amount of long-term borrowings as of the balance sheet date. May include notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, which had initial maturities beyond one year or beyond the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 20, 22
-Article 5

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year or the normal operating cycle, if longer plus capital lease obligations due to be paid more than one year after the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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-Section 02
-Paragraph 22
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
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The cash outflow for the settlement of borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, as it matures.

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Including both current and noncurrent portions, carrying amount as of the balance-sheet date of other forms of debt not elsewhere specified in the taxonomy with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
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The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

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The amount by which the debt instruments's fair value exceeds its carrying value or carrying value exceeds its fair value at the balance sheet date.

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The purchase price of the senior debt being repurchased per $1,000 of principal.

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The denomination which purchase price of senior debt is based upon.

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Represents the price to the public for senior notes issued.

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Carrying value of the senior note or debenture as of the balance sheet date.

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Total principal amount of senior debt issued during the period.

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Debt (Details) (USD $)	3 Months Ended			9 Months Ended
Debt (Details) (USD $)	Jun. 30, 2011	Mar. 31, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010	Sep. 30, 2010
Debt Instrument [Line Items]
Fair Value of Company's senior notes and debentures	$ 672,000,000			$ 672,000,000
Loss on extinguishment of debt	0		0	(87,000,000)	0
Maturities of Senior Debt	193,000,000
Unamortized net discount related to senior notes and debentures	32,000,000			32,000,000
Capital lease and other obligations	418,000,000			418,000,000		432,000,000
Total Debt	6,954,000,000			6,954,000,000		6,752,000,000
Less current portion	(26,000,000)			(26,000,000)		(31,000,000)
Total noncurrent portion	6,928,000,000			6,928,000,000		6,721,000,000
Purchase price of senior debt		1,153.50
Purchase price principal base		1,000
Senior debt repurchased		582,000,000
Total senior debt issued		1,000,000,000
Net cash proceeds from offerings		488,000,000
Line Of Credit Facility Abstract
Total Credit Facility Capacity	2,000,000,000			2,000,000,000
Minimum Interest Coverage Ratio				3.0x
Senior Notes 2011 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	0			0		193,000,000
Coupon rate	5.75%			5.75%
Senior Notes 2014 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	597,000,000			597,000,000		597,000,000
Coupon rate	4.375%			4.375%
Senior Notes 2015 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	250,000,000			250,000,000		250,000,000
Coupon rate	4.25%			4.25%
Senior Notes 2016 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	916,000,000			916,000,000		1,496,000,000
Coupon rate	6.25%			6.25%
Principal amount of senior notes		1,500,000,000
Senior Notes April 2017 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	496,000,000			496,000,000		0
Coupon rate	3.50%			3.50%
Principal amount of senior notes		500,000,000
Rate premium discount senior debt		99.139%
Senior Notes October 2017 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	498,000,000			498,000,000		497,000,000
Coupon rate	6.125%			6.125%
Senior Notes 2019 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	553,000,000			553,000,000		554,000,000
Coupon rate	5.625%			5.625%
Senior Debentures 2036 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	1,736,000,000			1,736,000,000		1,735,000,000
Coupon rate	6.875%			6.875%
Senior Debentures 2037 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	248,000,000			248,000,000		248,000,000
Coupon rate	6.75%			6.75%
Senior Debentures 2055 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	750,000,000			750,000,000		750,000,000
Coupon rate	6.85%			6.85%
Senior Notes 2021 [Member]
Debt Instrument [Line Items]
Senior notes and debentures	492,000,000			492,000,000		0
Coupon rate	4.50%			4.50%
Principal amount of senior notes		$ 500,000,000
Rate premium discount senior debt		98.32%