| **Stockholders' Equity and Statutory Accounting Practices (Narrative) (Details) - USD ($) $ in Millions**                                                       | 12 Months Ended |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|-----------------|
||
| **Stockholders' Equity and Statutory Accounting Practices [Abstract]**                                                                                          |            |   |
| Increase in statutory capital and surplus due to prescribed practice                                                                                            | $ 67            | $ 90 |
| Statutory Accounting Practices, Statutory Amount Available for Dividend Payment Before Consideration of Statutory Dividends Paid in the preceding twelve months | 1,075           |   |
| Statutory Accounting Practices, Dividends Paid in the preceding twelve months                                                                                   | $ 765           |   |
| Capital Required for Capital Adequacy to Risk Weighted Assets                                                                                                   | 270.00%         | 266.00% |

| X                                                                                                                                                                                                                                                                                                                                     |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Statutory Accounting Practices, Dividends Paid in the preceding twelve months
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Statutory Accounting Practices, Statutory Amount Available for Dividend Payments Before Consideration of Statutory Dividends Paid in the preceding twelve months
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Stockholders' Equity and Statutory Accounting Practices
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amount as of the balance sheet date of each item listed to reconcile the differences resulting from applying state prescribed statutory accounting practices rather than statutory accounting practices prescribed by National Association of Insurance Commissioners.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 505 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24746-158529
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