| **Shareholders' Equity And Dividend Restrictions (Change In AOCI Includes Changes In Unrealized Gains And Losses On Investments And Pension Obligations) (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Accumulated other comprehensive income before tax**                                                                                                                                                               |            |   |   |
| Accumulated unrealized gains, net, on investments available for sale, before tax                                                                                                                                    | $ 1,875         | $ 1,489 | $ 1,250 |
| Other Comprehensive Income (Loss), before Reclassifications, before Tax                                                                                                                                             | 537             | 426 | 303 |
| Reclassification adjustment for (gains) losses included in net income, before tax                                                                                                                                   | (77)            | (40) | (64) |
| Accumulated unrealized gains, net, on investments available for sale, before tax                                                                                                                                    | 2,335           | 1,875 | 1,489 |
| Accumulated unrealized losses for pension obligations, before tax                                                                                                                                                   | (101)           | (88) | (63) |
| Effect on other comprehensive income, before tax                                                                                                                                                                    | 83              | (13) | (25) |
| Accumulated unrealized losses for pension obligations, before tax                                                                                                                                                   | (18)            | (101) | (88) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, before Tax                                                            | (50)            | (29) | (18) |
| Other Comprehensive Income (Loss), before Reclassifications, Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, before Tax                                              | 40              | (19) | (5) |
| Other Comprehensive Income (Loss), Reclassification Adjustment for Life Deferred Acquisition Costs, Life Policy Reserves and Other, Before Tax                                                                      | (6)             | (2) | (6) |
| Other Comprehensive Income (Loss), Deferred Acquisition Costs, Life Policy Reserves and Other Adjustment, before Tax                                                                                                | 34              | (21) | (11) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, before Tax                                                            | (16)            | (50) | (29) |
| Accumulated other comprehensive income, before tax                                                                                                                                                                  | 1,724           | 1,372 | 1,169 |
| Change in unrealized gains, net, on investments available for sale, before tax                                                                                                                                      | 460             | 386 | 239 |
| Accumulated other comprehensive income, before tax                                                                                                                                                                  | 2,301           | 1,724 | 1,372 |
| **Accumulated other comprehensive income, tax**                                                                                                                                                                     |            |   |   |
| Accumulated unrealized gains, net, on investments available for sale, tax                                                                                                                                           | 647             | 512 | 428 |
| Other Comprehensive Income (Loss), Before Reclassifications, Tax                                                                                                                                                    | 188             | 149 | 106 |
| Reclassification adjustment for (gains) losses included in net income                                                                                                                                               | (27)            | (14) | (22) |
| Effect on other comprehensive income, tax                                                                                                                                                                           | 161             | 135 | 84 |
| Accumulated unrealized gains, net, on investments available for sale, tax                                                                                                                                           | 808             | 647 | 512 |
| Accumulated unrealized losses for pension obligations at end of period                                                                                                                                              | (6)             | (35) | (31) |
| Change in pension obligations                                                                                                                                                                                       | 29              | (4) | (9) |
| Accumulated unrealized losses for pension obligations at beginning of period                                                                                                                                        | (35)            | (31) | (22) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gain (Loss) On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Tax                                                                    | (17)            | (10) | (6) |
| Other Comprehensive Income (Loss), before Reclassifications, Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Tax                                                     | 14              | (7) | (2) |
| Reclassification adjustment for life deferred acquisition costs, life policy reserves and other, net, included in net income, tax                                                                                   | (2)             | 0 | (2) |
| Changes in life deferred acquisition costs, tax                                                                                                                                                                     | 12              | (7) | (4) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gain (Loss) On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Tax                                                                    | (5)             | (17) | (10) |
| Accumulated other comprehensive income at beginning of period                                                                                                                                                       | 595             | 471 | 400 |
| Effect on comprehensive income, tax                                                                                                                                                                                 | 202             | 124 | 71 |
| Accumulated other comprehensive income at end of period                                                                                                                                                             | 797             | 595 | 471 |
| **Accumulated other comprehensive income net of tax**                                                                                                                                                               |            |   |   |
| Accumulated Other Comprehensive Income Loss Unrealized Gains Losses On Available For Sale Securities Net Of Tax                                                                                                     | 1,228           | 977 | 822 |
| Other Comprehensive Income (Loss), before Reclassifications, Net of Tax                                                                                                                                             | 349             | 277 | 197 |
| Reclassification adjustment for (gains) losses included in net income, net of tax                                                                                                                                   | (50)            | (26) | (42) |
| Accumulated Other Comprehensive Income Loss Unrealized Gains Losses On Available For Sale Securities Net Of Tax                                                                                                     | 1,527           | 1,228 | 977 |
| Accumulated unrealized losses for pension obligations at beginning of period, net of tax                                                                                                                            | (66)            | (57) | (41) |
| Effect on other comprehensive income, net of tax                                                                                                                                                                    | 54              | (9) | (16) |
| Accumulated unrealized losses for pension obligations at beginning of period, net of tax                                                                                                                            | (12)            | (66) | (57) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gain (Loss) On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Net of Tax                                                             | (33)            | (19) | (12) |
| Other Comprehensive Income (Loss), before Reclassifications, Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Net of Tax                                              | 26              | (12) | (3) |
| Reclassification adjustment for life deferred acquisition costs, life policy reserves and other, net, included in net income, net of tax                                                                            | (4)             | (2) | (4) |
| Other Comprehensive Income (Loss), Deferred Acquistion Costs And Life Policy Reserves And Other, Net of Tax, Period Increase (Decrease)                                                                             | 22              | (14) | (7) |
| Accumulated Other Comprehensive Income (Loss), Unrealized Gain (Loss) On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Net of Tax                                                             | (11)            | (33) | (19) |
| Accumulated other comprehensive income at beginning of period, net of tax                                                                                                                                           | 1,129           | 901 | 769 |
| Change in unrealized gains, net, on investments available for sale, net of tax                                                                                                                                      | 299             | 251 | 155 |
| Effect on other comprehensive income, net of tax                                                                                                                                                                    | 375             | 228 | 132 |
| Accumulated other comprehensive income at beginning of period, net of tax                                                                                                                                           | 1,504           | 1,129 | 901 |
| Increase Decrease In Other Comprehensive Income Loss Before Tax                                                                                                                                                     | $ 577           | $ 352 | $ 203 |

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Other Comprehensive Income (Loss), before Reclassifications, Unrealized Gains Losses On Life Deferred Acquisition Costs And Life Policy Reserves And Other, Tax
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Other Comprehensive Income (Loss), Reclassification Adjustment for Life Deferred Acquisition Costs, Life Policy Reserves and Other, Before Tax
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| - Definition
The total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.
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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.
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The pretax total of net gain (loss), prior service cost (credit), and transition assets (obligations), as well as minimum pension liability if still remaining, included in accumulated other comprehensive income associated with a defined benefit pension or other postretirement plan(s) because they have yet to be recognized as components of net periodic benefit cost.
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Amount before tax and reclassification adjustments of other comprehensive income (loss).
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Amount after tax, before reclassification adjustments of other comprehensive income (loss).
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Amount of tax (expense) benefit, after reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.
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