Amortized Cost and Estimated Fair Value of Marketable Securities by Contractual Maturity (Detail) (USD $) In Millions |
Sep. 30, 2011 |
Dec. 31, 2010 |
|---|---|---|
| Cost | ||
| Due in one year or less | $ 686 | |
| Due after one year through three years | 192 | |
| Due after three years through five years | 85 | |
| Due after five years | 346 | |
| Marketable Securities, Debt Maturities, Amortized Cost, Total | 1,309 | |
| Equity securities | 1 | |
| Marketable Securities, Amortized Cost, Total | 1,310 | |
| Estimated Fair Value | ||
| Due in one year or less | 685 | |
| Due after one year through three years | 193 | |
| Due after three years through five years | 85 | |
| Due after five years | 356 | |
| Marketable Securities, Debt Maturities, Fair Value, Total | 1,319 | |
| Equity securities | 1 | |
| Estimated Fair Value | $ 1,320 | $ 883 |
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- Definition This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any.
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- Definition Marketable Securities, Amortized Cost [Abstract]
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- Definition This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after five years from the balance sheet date and which are categorized as marketable.
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- Definition This item represents the fair value of debt securities which are expected to mature after five years from the balance sheet date which are categorized as marketable.
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- Definition This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after one year and through three years from the balance sheet date and which are categorized as marketable.
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- Definition This item represents the fair value of debt securities which are expected to mature after one year and through three years from the balance sheet date and which are categorized as marketable.
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- Definition This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature after three years and through five years from the balance sheet date and which are categorized as marketable.
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- Definition This item represents the fair value of debt securities which are expected to mature after three years and through five years from the balance sheet date and which are categorized as marketable.
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- Definition This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified as marketable.
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- Definition This item represents the total of all debt securities grouped by maturity dates, at fair value, which are categorized as marketable.
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- Definition This item represents debt securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are expected to mature within one year of the balance sheet date and which are categorized as marketable.
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- Definition This item represents the fair value of debt securities which are expected to mature within one year of the balance sheet date and which are categorized as marketable.
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- Definition This item represents the total of all equity securities, at cost, net of adjustments made for accretion, amortization, other-than-temporary impairments, and hedging, if any, which are classified as marketable.
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- Definition This item represents the total of all equity securities, at fair value, which are categorized as marketable.
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- Definition Marketable Securities, Fair Value [Abstract]
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- Definition Total debt and equity financial instruments including: (1) securities held-to-maturity, (2) trading securities, and (3) securities available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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