Investments - Summary of Cost and Carrying Value of Investments Classified as Available-for-Sale Investments (Detail) - USD ($) $ in Millions |
Dec. 31, 2015 |
Dec. 31, 2014 |
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| Investments Debt And Equity Securities [Abstract] | ||
| Available-for-sale investments, Cost | $ 45 | $ 205 |
| Available-for-sale investments, Gross Unrealized Gains | 2 | 5 |
| Available-for-sale investments, Gross Unrealized Losses | (3) | (9) |
| Available-for-sale investments, Carrying Value | $ 44 | $ 201 |
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- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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