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Investments (Held-To-Maturity Securities Disclosure) (Details) (USD $) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2013 Securities | Dec. 31, 2012
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | $ 419,932,000 | $ 550,143,000
Net Unrealized Gains (Losses) | 2,030,000 | 3,926,000
Carrying Value | 421,962,000 | 554,069,000
Unrecognized Holding Gains | 26,567,000 | 40,615,000
Unrecognized Holding Losses | 0 | (23,000)
Fixed maturity securities, held-to-maturity, fair value | 448,529,000 | 594,661,000
Held To Maturity securities average duration | 2 years 3 months 18 days |
Number of held to maturity securities transferred to available-for-sale | 16 |
Securities reclassified from the HTM category to AFS carrying value | 39,600,000 |
Securities reclassified from the HTM category to AFS net unrecognized gain | 1,400,000 |
Foreign Government [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 5,292,000 | 5,292,000
Net Unrealized Gains (Losses) | 151,000 | 212,000
Carrying Value | 5,443,000 | 5,504,000
Unrecognized Holding Gains | 122,000 | 367,000
Unrecognized Holding Losses | 0 | 0
Fixed maturity securities, held-to-maturity, fair value | 5,565,000 | 5,871,000
Obligations of States and Political Subdivisions [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 372,281,000 | 491,180,000
Net Unrealized Gains (Losses) | 4,065,000 | 6,769,000
Carrying Value | 376,346,000 | 497,949,000
Unrecognized Holding Gains | 19,297,000 | 28,996,000
Unrecognized Holding Losses | 0 | (23,000)
Fixed maturity securities, held-to-maturity, fair value | 395,643,000 | 526,922,000
Corporate Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 29,228,000 | 38,285,000
Net Unrealized Gains (Losses) | (466,000) | (812,000)
Carrying Value | 28,762,000 | 37,473,000
Unrecognized Holding Gains | 3,015,000 | 4,648,000
Unrecognized Holding Losses | 0 | 0
Fixed maturity securities, held-to-maturity, fair value | 31,777,000 | 42,121,000
Asset-backed Securities [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 5,890,000 | 6,980,000
Net Unrealized Gains (Losses) | (755,000) | (1,052,000)
Carrying Value | 5,135,000 | 5,928,000
Unrecognized Holding Gains | 776,000 | 1,170,000
Unrecognized Holding Losses | 0 | 0
Fixed maturity securities, held-to-maturity, fair value | 5,911,000 | 7,098,000
Commercial Mortgage-backed Securities (CMBS) [Member] |  |
Schedule of Held-to-maturity Securities [Line Items] |  |
Amortized Cost | 7,241,000 | 8,406,000
Net Unrealized Gains (Losses) | (965,000) | (1,191,000)
Carrying Value | 6,276,000 | 7,215,000
Unrecognized Holding Gains | 3,357,000 | 5,434,000
Unrecognized Holding Losses | 0 | 0
Fixed maturity securities, held-to-maturity, fair value | $ 9,633,000 | $ 12,649,000

X
- Definition This item represents debt securities categorized as held-to-maturity, at cost, net of adjustments made for amortization and net unrealized gains (losses) resulting from: (i) other-than-temporary impairments and (ii) a previous available-for-sale designation. + References No definition available. + Details
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- Definition Held to maturity securities average duration. + References No definition available. + Details
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- Definition As of the balance sheet date, the excess of fair value over carrying value of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding gain. + References No definition available. + Details
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- Definition As of the balance sheet date, the excess of carrying value over fair value of a debt security categorized as held-to-maturity, exclusive of dividend or interest income recognized but not yet received and exclusive of any write-downs for other-than-temporary impairment. Such item represents the gross unrecognized holding loss. + References No definition available. + Details
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- Definition The remaining aggregate increase (decrease) in the market value of held-to-maturity securities either (i) prior to the securities' transfer to a held-to-maturity designation or (ii) resulting from a non-credit other-than-temporary impairment. + References No definition available. + Details
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- Definition This item represents the number of held-to-maturity securities reclassified to available-for-sale securities due to an unanticipated significant deterioration in credit quality. + References No definition available. + Details
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- Definition Amount after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=28360136&loc=d3e22054-111558 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 4: 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) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.6) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition Fair value of investments in debt securities classified as held-to-maturity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563 + Details
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- Definition For any transfer of securities categorized as held-to-maturity, this item represents the net carrying amount of the transferred security to another category of investments in debt and equity securities (trading or available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563 + Details
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- Definition This item represents the unrealized gain (loss) recognized in other comprehensive income (a separate component of shareholders' equity) as a result of securities categorized as held-to-maturity being transferred to the available-for-sale securities category. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27405-111563 + Details
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