Financings (Contingently Convertible Securities) (Details) (USD $) In Millions, except Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2011
Number of trading days, adjusted trigger price contingencies were met	20
Number of trading days	30
2.875% Senior Notes [Member]
Maturity Date	2024
Outstanding	$ 288
Adjusted Conversion Price	$ 12.81
Adjusted Trigger Price	$ 15.37
Senior Notes Interest Rate	2.875%
5.50% Senior Notes [Member]
Maturity Date	2029
Outstanding	172
Adjusted Conversion Price	$ 14.26
Adjusted Trigger Price	$ 18.54
Senior Notes Interest Rate	5.50%
3.375% Contingently Convertible Senior Notes due 2023 [Member]
Senior Notes Interest Rate	3.375%
Conversion Date	January 2011
Principal Converted	4
Conversion Value per share of principal	$ 1,994.21
Common Stock Issued on Settlement	197,472
Cash Paid on Settlement	$ 4

The price of the company's common stock which would be required to be attained for the conversion feature imbedded in the debt instrument to become effetive.

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Conversion Date

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The price per note of the conversion feature of the debt instrument.

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Principal amount of debt converted into another form of financial instrument during the period.

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- Definition

Number of trading days

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Number of trading days, adjusted trigger price contingencies were met

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Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-SubTopic 210
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- Definition

The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 32
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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The price per share of the conversion feature embedded in the debt instrument.

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Interest rate stated in the contractual debt agreement.

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- Definition

Description of the maturity date of the debt instrument including whether the debt matures serially and, if so, a brief description of the serial maturities.

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-Publisher FASB
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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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