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Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) (USD $) In Thousands, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2011 years | Dec. 31, 2010
Fair value, Beginning balance | $ 5,187 |  | $ 12,300 |
Total net gains (losses) for the period included in OCI | 507 | [1] | 1,840 | [1]
Total net gains (losses) for the period included in net income | (960) | [2],[3] | (5,419) | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (1,168) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | 751 |
Net transfers in and/or out of Level 3 | 24,344 |  | (4,285) |
Fair value, Ending balance | 27,910 |  | 5,187 |
Period over which proceeds are scheduled to be received | 10 |  |  |
AFS Fixed Maturity Securities [Member] | Corporate Securities [Member] |  |  |  |
Fair value, Beginning balance | 0 |  |  |
Total net gains (losses) for the period included in OCI | 0 | [1] |  |
Total net gains (losses) for the period included in net income | 0 | [2],[3] |  |
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | 0 |  |  |
Net transfers in and/or out of Level 3 | 2,603 |  |  |
Fair value, Ending balance | 2,603 |  |  |
AFS Fixed Maturity Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |  |
Fair value, Beginning balance | 0 |  |  |
Total net gains (losses) for the period included in OCI | 0 | [1] |  |
Total net gains (losses) for the period included in net income | 0 | [2],[3] |  |
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | 0 |  |  |
Net transfers in and/or out of Level 3 | 21,741 |  |  |
Fair value, Ending balance | 21,741 |  |  |
AFS Fixed Maturity Securities [Member] | Asset-backed Securities ("ABS") [Member] |  |  |  |
Fair value, Beginning balance |  |  | 0 |
Total net gains (losses) for the period included in OCI |  |  | (22) | [1]
Purchases, sales, issuances, and settlements (net) |  |  | 2,737 |
Net transfers in and/or out of Level 3 |  |  | (2,715) |
Fair value, Ending balance |  |  | 0 |
AFS Fixed Maturity Securities [Member] | Commercial Mortgage-backed Securities ("CMBS") [Member] |  |  |  |
Fair value, Beginning balance | 185 |  | 0 |
Total net gains (losses) for the period included in OCI | 507 | [1] | 1,862 | [1]
Total net gains (losses) for the period included in net income | (322) | [2],[3] | 41 | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (16) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | (148) |
Net transfers in and/or out of Level 3 | 0 |  | (1,570) |
Fair value, Ending balance | 354 |  | 185 |
Receivable For Proceeds From Divestiture Of Businesses [Member] |  |  |  |
Fair value, Beginning balance | 5,002 |  | 12,300 |
Total net gains (losses) for the period included in OCI | 0 | [1] | 0 | [1]
Total net gains (losses) for the period included in net income | (638) | [2],[3] | (5,460) | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (1,152) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | (1,838) |
Net transfers in and/or out of Level 3 | 0 |  | 0 |
Fair value, Ending balance | $ 3,212 |  | $ 5,002 |
[1] | Amounts are reported in "Other net unrealized gains on investment securities, net of deferred income tax" on the Consolidated Statements of Stockholders' Equity.
[2] | Amounts are reported in "Net realized gains (losses)" for realized gains and losses and "Net investment income earned" for amortization for the CMBS securities on the Consolidated Statements of Income.
[3] | Amounts are reported in either "Loss on disposal of discontinued operations, net of tax" or "Other income" for the receivable related to the sale of Selective HR on the Consolidated Statements of Income. Amounts in "Loss on disposal of discontinued operations, net of tax" relate to charges to reduce the fair value of our receivable and amounts in "Other income" related to interest accretion on the receivable.

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- Definition This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in earnings or resulted in a change in net asset value. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(1) -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 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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- Definition This element represents total gains or losses for the period (realized and unrealized), arising from assets measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -Subparagraph c(1) -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 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258 + Details
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