Marketable Securities Narrative (Details) - USD ($) $ in Millions |
Mar. 31, 2017 |
Dec. 31, 2016 |
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Investments, Debt and Equity Securities [Abstract] | ||
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 485 | $ 265 |
Trading Securities | $ 17 | $ 13 |
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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