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Investments (Schedule Of Cost And Fair Value Of Equity Securities) (Detail) - USD ($) $ in Millions | Jun. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Investments, Debt and Equity Securities [Abstract] |  |
Cost | $ 433 | $ 440
Gross unrealized appreciation | 77 | 83
Gross unrealized depreciation | (12) | (13)
Fair value | $ 498 | $ 510

X
- Definition As of the balance sheet date, the excess of fair value over carrying value (amortized cost) of an equity security , exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding gain. + References No definition available. + Details
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X
- Definition As of the balance sheet date, the excess of carrying value (amortized cost) over fair value of an equity security, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding loss. + References No definition available. + Details
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X
- Definition This item represents the cost of equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments for other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any. + References No definition available. + Details
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- Definition Amount of equity securities categorized neither as held-to-maturity nor as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=51813488&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49167202&loc=d3e26610-111562 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803 + Details
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- References No definition available. + Details
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