| **Fair Value (Carrying amount and estimated fair value of financial instrument assets and liabilities which are not measured at fair value) (Details) (USD $)In Millions, unless otherwise specified** | Mar. 31, 2013 | Dec. 31, 2012 |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      | $ 20          | $ 21          |
| Mortgage loans                                                                                                                                                                                         | 425           | 401           |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Short term debt                                                                                                                                                                                        | 13            | 13            |
| Long term debt                                                                                                                                                                                         | 2,558         | 2,557         |
| Carrying Amount [Member]                                                                                                                                                                               |          |          |
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      | 20            | 21            |
| Mortgage loans                                                                                                                                                                                         | 425           | 401           |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Premium deposits and annuity contracts                                                                                                                                                                 | 96            | 100           |
| Short term debt                                                                                                                                                                                        | 13            | 13            |
| Long term debt                                                                                                                                                                                         | 2,558         | 2,557         |
| Estimated Fair Value [Member]                                                                                                                                                                          |          |          |
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      | 20            | 21            |
| Mortgage loans                                                                                                                                                                                         | 449           | 418           |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Premium deposits and annuity contracts                                                                                                                                                                 | 100           | 104           |
| Short term debt                                                                                                                                                                                        | 13            | 13            |
| Long term debt                                                                                                                                                                                         | 3,016         | 3,016         |
| Level 1 [Member] | Estimated Fair Value [Member]                                                                                                                                                       |          |          |
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      |     |     |
| Mortgage loans                                                                                                                                                                                         |     |     |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Premium deposits and annuity contracts                                                                                                                                                                 |     |     |
| Short term debt                                                                                                                                                                                        |     |     |
| Long term debt                                                                                                                                                                                         |     |     |
| Level 2 [Member] | Estimated Fair Value [Member]                                                                                                                                                       |          |          |
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      |     |     |
| Mortgage loans                                                                                                                                                                                         |     |     |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Premium deposits and annuity contracts                                                                                                                                                                 |     |     |
| Short term debt                                                                                                                                                                                        | 13            | 13            |
| Long term debt                                                                                                                                                                                         | 3,016         | 3,016         |
| Level 3 [Member] | Estimated Fair Value [Member]                                                                                                                                                       |          |          |
| **Financial Assets [Abstract]**                                                                                                                                                                        |          |          |
| Notes receivable for the issuance of common stock                                                                                                                                                      | 20            | 21            |
| Mortgage loans                                                                                                                                                                                         | 449           | 418           |
| **Financial Liabilities [Abstract]**                                                                                                                                                                   |          |          |
| Premium deposits and annuity contracts                                                                                                                                                                 | 100           | 104           |
| Short term debt                                                                                                                                                                                        |     |     |
| Long term debt                                                                                                                                                                                         |     |     |

| X                                                                                                                                                                                                                                                             |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Premium deposits and annuity contracts
+ References
No definition available.
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| X                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                         |
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount of long-term debt, net of unamortized discount or premium, scheduled to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
+ 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 210.5-02.19,20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying amount of long-term debt, net of unamortized discount or premium, excluding amounts to be repaid within one year or the normal operating cycle, if longer (current maturities). Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.
+ 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 210.5-02.22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 60 -Paragraph 47 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 2: 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(c)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph c -Article 7
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Amounts receivable from officers and directors resulting from the sale of stock to officers or directors before the cash payment is received.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section EReference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29,30) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 4.E) -URI http://asc.fasb.org/extlink&oid=6228006&loc=d3e74512-122707
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