Marketable Securities (Available-for-Sale Debt Securities by Contractual Maturity) (Details) - USD ($) $ in Millions |
Mar. 31, 2017 |
Dec. 31, 2016 |
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Investments, Debt and Equity Securities [Abstract] | ||
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Fair Value | $ 405 | |
Available-for-sale Securities, Debt Maturities, Year Two Through Three, Fair Value | 383 | |
Available-for-sale Securities, Debt Securities | $ 788 | $ 433 |
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- Definition Available-for-sale Securities, Debt Maturities, Year Two Through Three, Fair Value No definition available.
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- Definition Fair value of available-for-sale debt securities maturing in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of debt securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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