Investments (Roll-Forward Of Pre-Tax Credit Losses Related To Fixed Maturities For Which Portion Of Other-Than-Temporary Impairment Was Recognized In Other Comprehensive Income) (Detail) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
|
| Roll-Forward Of Pre-Tax Credit Losses Related To Fixed Maturities For Which Portion Of Other-Than-Temporary Impairment Was Recognized In Other Comprehensive Income [Roll Forward] | ||||
| Balance of credit losses related to securities still held – beginning of period | $ 22 | $ 35 | $ 28 | $ 37 |
| Additions where no OTTI was previously recorded | 4 | 5 | 7 | 7 |
| Additions where an OTTI was previously recorded | 1 | 1 | 2 | 3 |
| Reductions for securities sold during the period | (4) | (17) | (14) | (23) |
| Balance of credit losses related to securities still held – end of period | $ 23 | $ 24 | $ 23 | $ 24 |