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Investments In Debt And Equity Securities (Narrative) (Details) (USD $)
In Millions, unless otherwise specified |
Mar. 31, 2013
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Dec. 31, 2012
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| Schedule of Investments [Line Items] | ||
| Short-term investments | $ 288 | $ 333 |
| Trading Securities | 25 | 33 |
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Auction Rate Securities [Member]
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| Schedule of Investments [Line Items] | ||
| Long-term investments, carrying value | 28 | 29 |
| Long-term investments, par value | $ 34 | $ 34 |
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- Definition
Long Term Investments Par Value No definition available.
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- Definition
The total amount of investments that are intended to be held for an extended period of time (longer than one operating cycle). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The total of financial instruments that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for debt and equity securities formerly categorized as available-for-sale or held-to-maturity which the entity held as of the date it opted to account for such securities at fair value. An enterprise may also categorize such a security as trading without the intent to sell it in the near term assuming the decision to categorize the security as trading occurred at acquisition. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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