| **Debt (Details) (USD $)**                                                | 6 Months Ended       | 12 Months Ended |                      |
|---------------------------------------------------------------------------|----------------------|-----------------|----------------------|
||
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | $ 5,237,000,000      |                 | $ 4,843,000,000      |  |   |
| Unamortized Discount                                                      | (18,000,000)         |                 | (19,000,000)         |  |   |
| Total Debt, Net of Discount                                               | 5,219,000,000        |                 | 4,824,000,000        |  |   |
| Current Portion of Long Term Debt, net of discount                        | 0                    | [1]             | (200,000,000)        | [1] |   |
| Capital Lease Obligations, Current                                        | (59,000,000)         | [1]             | (58,000,000)         | [1] |   |
| Long-term Debt Due After One Year                                         | 5,160,000,000        |                 | 4,566,000,000        |  |   |
| Credit Facility due October 3, 2018 [Member]                              |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 600,000,000          |                 | 0                    |  |   |
| Interest Rate (percentage in hundredths)                                  | 1.41%                |                 | 0.00%                |  |   |
| Debt instrument, maturity date                                            | Oct.				03,				 2018 |                 | Oct.				03,				 2018 |  |   |
| Revolving Credit Facility Maximum Borrowing Capacity                      | 4,000,000,000        |                 |                 |  |   |
| Credit facility fee rate basis points, minimum                            |                 |                 |                 |  | 0.125% |
| Credit facility fee rate basis points, maximum                            |                 |                 |                 |  | 0.30% |
| Credit facility aggregate short-term loans and letters of credit, maximum | 500,000,000          |                 |                 |  |   |
| Credit facility interest rate, Eurodollar rate plus, minimum              |                 |                 |                 |  | 1.00% |
| Credit facility interest rate, Eurodollar rate plus, maximum              |                 |                 |                 |  | 1.45% |
| Capital Lease and Other Obligations                                       |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 353,000,000          |                 | 359,000,000          |  |   |
| Interest Rate (percentage in hundredths)                                  | 0.00%                |                 | 0.00%                |  |   |
| Capital Lease Obligations, Current                                        | (59,000,000)         |                 | (58,000,000)         |  |   |
| 5¼% Senior Notes, due April 15, 2014                                 |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 0                    | [2]             | 200,000,000          |  |   |
| Interest Rate (percentage in hundredths)                                  | 0.00%                | [2]             | 5.25%                |  |   |
| Debt instrument, maturity date                                            | Apr. 15,				 2014    |                 | Apr. 15,				 2014    |  |   |
| Current Portion of Long Term Debt, net of discount                        | 0                    | [2]             | (200,000,000)        |  |   |
| 8¼% Senior Notes, due March 1, 2019                                  |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 1,000,000,000        |                 | 1,000,000,000        |  |   |
| Interest Rate (percentage in hundredths)                                  | 8.25%                |                 | 8.25%                |  |   |
| Debt instrument, maturity date                                            | Mar.				01,				 2019 |                 | Mar.				01,				 2019 |  |   |
| 4.15% Senior Notes, due December 15, 2021                                 |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 1,000,000,000        |                 | 1,000,000,000        |  |   |
| Interest Rate (percentage in hundredths)                                  | 4.15%                |                 | 4.15%                |  |   |
| Debt instrument, maturity date                                            | Dec. 15,				 2021    |                 | Dec. 15,				 2021    |  |   |
| 7¼% Senior Notes, due October 15, 2023                               |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 100,000,000          |                 | 100,000,000          |  |   |
| Interest Rate (percentage in hundredths)                                  | 7.25%                |                 | 7.25%                |  |   |
| Debt instrument, maturity date                                            | Oct. 15,				 2023    |                 | Oct. 15,				 2023    |  |   |
| 8% Senior Notes, due April 1, 2027                                        |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 250,000,000          |                 | 250,000,000          |  |   |
| Interest Rate (percentage in hundredths)                                  | 8.00%                |                 | 8.00%                |  |   |
| Debt instrument, maturity date                                            | Apr.				01,				 2027 |                 | Apr.				01,				 2027 |  |   |
| 6% Senior Notes, due March 1, 2041                                        |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 850,000,000          |                 | 850,000,000          |  |   |
| Interest Rate (percentage in hundredths)                                  | 6.00%                |                 | 6.00%                |  |   |
| Debt instrument, maturity date                                            | Mar.				01,				 2041 |                 | Mar.				01,				 2041 |  |   |
| 5¼% Senior Notes, due November 15, 2043                              |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | 1,000,000,000        |                 | 1,000,000,000        |  |   |
| Interest Rate (percentage in hundredths)                                  | 5.25%                |                 | 5.25%                |  |   |
| Debt instrument, maturity date                                            | Nov. 15,				 2043    |                 | Nov. 15,				 2043    |  |   |
| 7¼% Senior Debentures, due August 1, 2097                            |                 |                 |                 |  |   |
| **Debt Instrument [Line Items]**                                          |                 |                 |                 |  |   |
| Debt                                                                      | $ 84,000,000         |                 | $ 84,000,000         |  |   |
| Interest Rate (percentage in hundredths)                                  | 7.25%                |                 | 7.25%                |  |   |
| Debt instrument, maturity date                                            | Aug.				01,				 2097 |                 | Aug.				01,				 2097 |  |   |
|                                                                           |
| [1]See Note 6. Debt.[2]We repaid the Senior Notes on their due date.      |

| X                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Maximum incremental aggregate short-term loans and letters of credit capacity under the terms of a credit facility.
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| X                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Amount of the fee for available but unused credit capacity under the credit facility, maximum
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| X                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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Amount of the fee for available but unused credit capacity under the credit facility, minimum
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| - Definition
Adjustment maximum made to the stated Eurodollar rate to determine the effective rate.
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Adjustment minimum made to the stated Eurodollar rate to determine the effective rate.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of capital lease obligation due within one year or the normal operating cycle, if longer.
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations.
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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of long-term debt before deduction of unamortized discount or premium. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt, with initial maturities beyond one year or the normal operating cycle, if longer.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Contractual interest rate for funds borrowed, under the debt agreement.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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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| - Definition
Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer.
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| - Definition
Sum of the carrying values as of the balance sheet date of the portions of all long-term notes and loans payable due within one year or the operating cycle if longer.
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