Investments (Investment Income (Loss), Net) (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2016 |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Investments, Debt and Equity Securities [Abstract] | |||
| Gains on sales and exchanges of investments, net | $ 46 | $ 12 | $ 192 |
| Investment impairment losses | (34) | (59) | (50) |
| Unrealized gains (losses) on securities underlying prepaid forward sale agreements | 0 | 42 | 66 |
| Mark to market adjustments on derivative component of prepaid forward sale agreements and indexed debt instruments | (4) | (42) | (56) |
| Interest and dividend income | 123 | 115 | 116 |
| Other, net | 82 | 13 | 28 |
| Investment income (loss), net | $ 213 | $ 81 | $ 296 |
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- Definition Mark To Market Adjustment on Derivative Component Of Prepaid Forward Sale Agreements and indexed debt instruments. No definition available.
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- Definition Nonoperating income (losses), net from investment holdings recorded in the income statement that are not separately stated. No definition available.
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- Definition The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before accretion (amortization) of purchase discount (premium) of interest income and dividend income on nonoperating securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition The net realized gains or losses on investments during the period, not including gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of unrealized gain (loss) recognized in the income statement on unsold other securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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