v2.4.0.8

Fair Value Measurements (Financial Instruments Measured At Fair Value On Recurring Basis) (Detail) (USD $) In Millions, unless otherwise specified | Sep. 30, 2014 | Dec. 31, 2013
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Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | $ 49,148 |  | $ 49,254 |
Equity securities, at fair value | 546 |  | 837 |
Short-term investments | 2,753 |  | 1,763 |
Other investments | 3,259 |  | 2,976 |
Securities lending collateral | 1,440 |  | 1,632 |
Fair Value, Inputs, Level 1 [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 1,692 |  | 1,849 |
Equity securities, at fair value | 520 |  | 373 |
Short-term investments | 1,253 |  | 953 |
Other investments | 336 |  | 305 |
Investment derivative instruments, assets | 23 |  | 19 |
Other derivative instruments, assets | 11 |  | 0 |
Separate account assets | 1,389 |  | 1,145 |
Total assets measured at fair value | 5,224 |  | 4,644 |
Investment derivative instruments, liabilities | 5 |  | 6 |
Other derivative instruments, liability | 0 |  | 60 |
GLB | 0 | [1] | 0 | [1]
Total liabilities measured at fair value | 5 |  | 66 |
Fair Value, Inputs, Level 1 [Member] | U.S. Treasury And Agency [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 1,490 |  | 1,626 |
Fair Value, Inputs, Level 1 [Member] | Foreign [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 202 |  | 223 |
Fair Value, Inputs, Level 1 [Member] | Corporate Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 0 |  | 0 |
Fair Value, Inputs, Level 2 [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 47,221 |  | 47,187 |
Equity securities, at fair value | 24 |  | 460 |
Short-term investments | 1,500 |  | 803 |
Other investments | 252 |  | 231 |
Securities lending collateral | 1,440 |  | 1,632 |
Other derivative instruments, assets | 2 |  | 6 |
Separate account assets | 90 |  | 81 |
Total assets measured at fair value | 50,529 |  | 50,400 |
Investment derivative instruments, liabilities | 0 |  | 0 |
Other derivative instruments, liability | 2 |  | 2 |
GLB | 0 | [1] | 0 | [1]
Total liabilities measured at fair value | 2 |  | 2 |
Fair Value, Inputs, Level 2 [Member] | U.S. Treasury And Agency [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 1,188 |  | 1,323 |
Fair Value, Inputs, Level 2 [Member] | Foreign [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 15,017 |  | 14,324 |
Fair Value, Inputs, Level 2 [Member] | Corporate Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 17,130 |  | 17,304 |
Fair Value, Inputs, Level 2 [Member] | Mortgage Backed-Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 10,309 |  | 10,886 |
Fair Value, Inputs, Level 2 [Member] | States, Municipalities, And Political Subdivisions [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 3,577 |  | 3,350 |
Fair Value, Inputs, Level 3 [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 235 |  | 218 |
Equity securities, at fair value | 2 |  | 4 |
Short-term investments | 0 |  | 7 |
Other investments | 2,671 |  | 2,440 |
Other derivative instruments, assets | 0 |  | 0 |
Total assets measured at fair value | 2,908 |  | 2,669 |
Investment derivative instruments, liabilities | 0 |  | 0 |
Other derivative instruments, liability | 0 |  | 0 |
GLB | 317 | [1] | 193 | [1]
Total liabilities measured at fair value | 317 |  | 193 |
Fair Value, Inputs, Level 3 [Member] | U.S. Treasury And Agency [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 0 |  | 0 |
Fair Value, Inputs, Level 3 [Member] | Foreign [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 12 |  | 44 |
Fair Value, Inputs, Level 3 [Member] | Corporate Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 208 |  | 166 |
Fair Value, Inputs, Level 3 [Member] | Mortgage Backed-Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 15 |  | 8 |
Fair Value, Inputs, Level 3 [Member] | States, Municipalities, And Political Subdivisions [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 0 |  | 0 |
Estimate of Fair Value, Fair Value Disclosure [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 49,148 |  | 49,254 |
Equity securities, at fair value | 546 |  | 837 |
Short-term investments | 2,753 |  | 1,763 |
Other investments | 3,259 |  | 2,976 |
Securities lending collateral | 1,440 |  | 1,632 |
Investment derivative instruments, assets | 23 |  | 19 |
Other derivative instruments, assets | 13 |  | 6 |
Separate account assets | 1,479 |  | 1,226 |
Total assets measured at fair value | 58,661 |  | 57,713 |
Investment derivative instruments, liabilities | 5 |  | 6 |
Other derivative instruments, liability | 2 |  | 62 |
GLB | 317 | [1] | 193 | [1]
Total liabilities measured at fair value | 324 |  | 261 |
Estimate of Fair Value, Fair Value Disclosure [Member] | U.S. Treasury And Agency [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 2,678 |  | 2,949 |
Estimate of Fair Value, Fair Value Disclosure [Member] | Foreign [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 15,231 |  | 14,591 |
Estimate of Fair Value, Fair Value Disclosure [Member] | Corporate Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 17,338 |  | 17,470 |
Estimate of Fair Value, Fair Value Disclosure [Member] | Mortgage Backed-Securities [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | 10,324 |  | 10,894 |
Estimate of Fair Value, Fair Value Disclosure [Member] | States, Municipalities, And Political Subdivisions [Member] |  |  |  |
Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] |  |  |  |
Fixed maturities available for sale at fair value | $ 3,577 |  | $ 3,350 |
[1] | Our GLB reinsurance product meets the definition of a derivative instrument for accounting purposes and is accordingly carried at fair value. Excluded from the table above is the portion of the GLB derivative liability classified as Future policy benefits in the consolidated balance sheets. Refer to Note 5 for additional information.

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- Definition GMIB - The fair value of the benefit in long-duration contracts to provide a guaranteed minimum amount available for annuitization after a specified period, which is in addition to a guaranteed minimum annuity rate. GMAB - The guaranteed account value floor that is available to a contractor policy holder in cash + References No definition available. + Details
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- Definition The fair value for actively traded investment derivative instruments including futures, options, and exchange traded forward contracts reflected as an asset. + References No definition available. + Details
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- Definition The fair value of all other derivative instruments held by the Company. + References No definition available. + Details
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- Definition Separate account assets fair value + References No definition available. + Details
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- Definition Amount of debt securities categorized neither as held-to-maturity nor 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=28360136&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27161-111563 Reference 3: 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=6871852&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 320 -Section 50 -Paragraph 2 -Subparagraph (b)-(g) -URI http://asc.fasb.org/extlink&oid=6957658&loc=d3e62557-112803 + 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=28360136&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=6871852&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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- Definition Aggregation of the liabilities reported on the balance sheet measured at fair value on a recurring basis by the entity. + References No definition available. + Details
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- Definition Other long-term investments not otherwise specified in the taxonomy, not including investments in marketable securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.12) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 12 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(f)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph f -Article 7 + Details
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- Definition Other investments not otherwise specified in the taxonomy that will be realized in a short period of time, usually less than one year or the normal operating cycle, whichever is longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.5) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.1(g)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 5 -Article 9 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 + Details
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