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Fair Value Measurements (Changes in Fair Value of Securities Using Level 3 Inputs) (Details) (USD $) In Thousands | 6 Months Ended | 12 Months Ended
--- | --- | ---
Jun. 30, 2011 | Dec. 31, 2010
Fair value, Beginning balance | $ 5,187 |  | $ 12,300 |
Total net gains (losses) for the period included in OCI | 440 | [1] | 1,840 | [1]
Total net gains (losses) for the period included in net income | 20 | [2] | (5,419) | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (675) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | 751 |
Net transfers in and/or out of Level 3 | 0 |  | (4,285) |
Fair value, Ending balance | 4,972 |  | 5,187 |
Asset-backed Securities ("ABS") [Member] | AFS Fixed Maturity Securities [Member] |  |  |  |
Fair value, Beginning balance |  |  | 0 |
Total net gains (losses) for the period included in OCI |  |  | (22) | [1]
Total net gains (losses) for the period included in net income |  |  | 0 | [2],[3]
Purchases, sales, issuances, and settlements (net) |  |  | 2,737 |
Net transfers in and/or out of Level 3 |  |  | (2,715) |
Fair value, Ending balance |  |  | 0 |
Commercial Mortgage-backed Securities ("CMBS") [Member] | AFS Fixed Maturity Securities [Member] |  |  |  |
Fair value, Beginning balance | 185 |  | 0 |
Total net gains (losses) for the period included in OCI | 440 | [1] | 1,862 | [1]
Total net gains (losses) for the period included in net income | (179) | [2] | 41 | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (5) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | (148) |
Net transfers in and/or out of Level 3 | 0 |  | (1,570) |
Fair value, Ending balance | 441 |  | 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 | 199 | [2] | (5,460) | [2],[3]
Purchases | 0 |  |  |
Sales | 0 |  |  |
Issuances | 0 |  |  |
Settlements | (670) |  |  |
Purchases, sales, issuances, and settlements (net) |  |  | (1,838) |
Net transfers in and/or out of Level 3 | 0 |  | 0 |
Fair value, Ending balance | $ 4,531 |  | $ 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 investment gains (losses)" for the ABS and CMBS securities and "Other income" for the receivable related to the sale of Selective HR on the Consolidated Statements of Income.
[3] | Amounts are reported in "Loss on disposal of discontinued operations, net of tax" for the receivable related to sale of Selective HR on the Consolidated Statements of Income.

X
- Definition Issues that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + Details
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- Definition Purchases that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + Details
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- Definition Sales that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + Details
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- Definition Settlements that have taken place during the period in relation to assets measured at fair value and categorized within Level 3 of the fair value hierarchy. + 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 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) + 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) + Details
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- Definition This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3). + 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(2) + Details
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- Definition This element represents [net] transfers in to and out of assets measured at fair value on a recurring basis using unobservable inputs (Level 3) which have taken place during the period. + 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(3) + Details
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- Definition This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances. + 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 + Details
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