Investments (Details) - USD ($) $ in Millions |
Mar. 31, 2017 |
Dec. 31, 2016 |
|---|---|---|
| Schedule of Trading Securities and Other Trading Assets [Line Items] | ||
| Total trading securities | $ 400 | $ 384 |
| Trading Securities | ||
| Trading Securities Unrealized Holding Gains (Losses) | 51 | 39 |
| Marketable Securities | 296 | 282 |
| Other Assets | $ 104 | $ 102 |
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- Definition This element represents the fair value of trading securities included in the Marketable Securities caption in the statement of financial position. No definition available.
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- Definition This element represents the fair value of trading securities included in the Other Assets caption in the statement of financial position. No definition available.
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- References No definition available.
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- Definition For trading securities held as of the balance sheet date, this amount represents the difference between the fair value of trading securities and their cost basis (unrealized holding gain or loss). Trading securities are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) and such unrealized holding gain or loss is included in earnings for the period. No definition available.
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. 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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