| **Schedule of Other Intangible Assets (Details) - USD ($) $ in Millions** | 12 Months Ended |        |
|---------------------------------------------------------------------------|-----------------|--------|
||
| Indefinite-lived intangible assets                                        | $ 68            | $ 71   |
| Finite-Lived Intangible Assets                                            | 76              | 80     |
| Intangible Assets, Gross (Excluding Goodwill)                             | 144             | 151    |
| Accumulated Amortization                                                  | 63              | 66     |
| Lloyds syndicate capacity [Member]                                        |            |   |
| Indefinite-lived intangible assets                                        | 52              | 55     |
| Agency Force [Member]                                                     |            |   |
| Indefinite-lived intangible assets                                        | 16              | 16     |
| Value of business acquired [Member]                                       |            |   |
| Finite-Lived Intangible Assets                                            | 57              | 60     |
| Accumulated Amortization                                                  | $ 57            | 61     |
| Trade name [Member]                                                       |            |   |
| Economic useful life measured in years                                    | 8 years         |   |
| Finite-Lived Intangible Assets                                            | $ 7             | 8      |
| Accumulated Amortization                                                  | $ 3             | 3      |
| Distribution channel [Member]                                             |            |   |
| Economic useful life measured in years                                    | 15 years        |   |
| Finite-Lived Intangible Assets                                            | $ 12            | 12     |
| Accumulated Amortization                                                  | $ 3             | $ 2    |
| Minimum [Member] | Value of business acquired [Member]                    |            |   |
| Economic useful life measured in years                                    | 1 year          |   |
| Maximum [Member] | Value of business acquired [Member]                    |            |   |
| Economic useful life measured in years                                    | 4 years         |   |

| X                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
No definition available.
+ Details**Name:**us-gaap_FiniteLivedIntangibleAssetUsefulLife**Namespace Prefix:**us-gaap_**Data Type:**xbrli:durationItemType**Balance Type:**na**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
+ Details**Name:**us-gaap_FiniteLivedIntangibleAssetsGross**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275
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| X                                                                                                                                                                                                                                                                                                                  |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount before accumulated amortization of intangible assets, excluding goodwill.
+ References
No definition available.
+ Details**Name:**us-gaap_IntangibleAssetsGrossExcludingGoodwill**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                 |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                     |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                             |
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| X                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                            |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                               |
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| X                                                                                                                               |
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