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Investments (Number of Securities in an Unrealized Unrecognized Loss Position) (Details) $ in Thousands | Dec. 31, 2015 USD ($) Securities | Dec. 31, 2014 USD ($) Securities
--- | --- | ---
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Twelve Months or Longer |  | $ 116 | $ 439 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 0 | 196 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 141,580 | 442,058 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | (4,900) | (8,170) | [1]
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 1,449,183 | 466,387 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | $ (19,953) | $ (2,408) | [1]
Number of securities in an unrealized/unrecognized loss position | Securities |  | 609 | 350 |
Unrealized Unrecognized Loss |  | $ 24,859 | $ 10,596 |
Percentage Decline in Fair Value Percentage |  | 2.00% |  |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | $ 0 | (3) |
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Less Than Twelve Months |  | 0 | 1 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 805 | 2,235 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (122) | (455) |
Available For Sale and Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value |  | 1,449,183 | 466,583 |
Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Losses | [1] | (19,953) | (2,411) |
Held To Maturity And Available For Sale Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Less Than Twelve Months |  | 0 | 1 |
Available For Sale and Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value |  | 142,385 | 444,293 |
Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Twelve Months Or Longer Aggregate Losses | [1] | (5,022) | (8,625) |
Held To Maturity And Available For Sale Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position For Twelve Months Or Longer |  | $ 116 | $ 439 |
Eighty Percent to Ninety-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | Securities |  | 606 | 350 |
Unrealized Unrecognized Loss |  | $ 22,971 | $ 10,596 |
Sixty Percent to Seventy-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | Securities |  | 3 | 0 |
Unrealized Unrecognized Loss |  | $ 1,888 | $ 0 |
Forty Percent to Fifty-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | Securities |  | 0 | 0 |
Unrealized Unrecognized Loss |  | $ 0 | $ 0 |
Twenty Percent to Thirty-Nine Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | Securities |  | 0 | 0 |
Unrealized Unrecognized Loss |  | $ 0 | $ 0 |
Zero Percent to Nineteen Percent [Member] |  |  |  |
Number of securities in an unrealized/unrecognized loss position | Securities |  | 0 | 0 |
Unrealized Unrecognized Loss |  | $ 0 | $ 0 |
Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 141,580 | 442,058 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (4,900) | (8,170) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 1,416,504 | 461,125 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (17,915) | (2,072) |
Equity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 | 0 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 | 0 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 32,679 | 5,262 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | (2,038) | (336) |
U.S. Government and Government Agencies [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 396 | 10,866 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (4) | (115) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 16,006 | 7,567 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (87) | (13) |
Foreign Government [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | 0 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 1,067 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (2) |  |
Obligations of States and Political Subdivisions [Member] |  |  |  |
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Twelve Months or Longer |  |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  |  | 196 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] |  | (3) |
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Less Than Twelve Months |  |  | 1 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  |  | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] |  | 0 |
Obligations of States and Political Subdivisions [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 | 64,018 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | 0 | (624) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 28,617 | 47,510 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (160) | (105) |
Corporate Securities [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 50,382 | 153,613 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (2,850) | (4,075) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 761,479 | 276,648 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (12,671) | (1,734) |
Asset-backed Securities [Member] |  |  |  |
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Twelve Months or Longer |  | 116 | 439 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 0 | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | 0 | 0 |
Held To Maturity Securities Unrecognized Gains Losses Aggregate Continuous Unrealized Loss Position Less Than Twelve Months |  | 0 | 0 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 805 | 2,235 |
Held-to-maturity Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (122) | (455) |
Asset-backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 12,022 | 15,618 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (111) | (195) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 197,477 | 113,202 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (807) | (178) |
Commercial Mortgage Backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 15,385 | 59,219 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (214) | (743) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 146,944 | 12,799 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (2,196) | (34) |
Residential Mortgage Backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 63,395 | 138,724 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | [1] | (1,721) | (2,418) |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 264,914 | 3,399 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | [1] | (1,992) | (8) |
Common Stock [Member] | Equity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 | 0 |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 | 0 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 31,148 | 5,262 |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | (1,998) | $ (336) |
Nonredeemable Preferred Stock [Member] | Equity Securities [Member] |  |  |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value |  | 0 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss |  | 0 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value |  | 1,531 |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss |  | $ (40) |  |
[1] | Gross unrealized losses include non-OTTI unrealized amounts and OTTI losses recognized in AOCI. In addition, this column includes remaining unrealized gain or loss amounts on securities that were transferred to an HTM designation in the first quarter of 2009 for those securities that are in a net unrealized/unrecognized loss position.

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- Definition This item represents the unrealized holding gains/losses of an available-for sale ("AFS") and held-to-maturity("HTM") security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The AFS unrealized holding losses represent the excess of amortized cost over fair value of securities. The HTM unrealized holding gains/losses represent the remaining unrealized gain/loss amounts on securities that were transferred to a HTM designation from an AFS designation as well as other-than-temporary impairment losses that are recognized in accumulated other comprehensive income. + References No definition available. + Details
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- Definition This item represents the unrealized holding gains/losses of an available-for sale ("AFS") and held-to-maturity("HTM") security that has been in a continuous unrealized/unrecognized loss position for twelve months or longer. The AFS unrealized holding losses represent the excess of amortized cost over fair value of securities. The HTM unrealized holding gains/losses represent the remaining unrealized gain/loss amounts on securities that were transferred to a HTM designation from an AFS designation as well as other-than-temporary impairment losses that are recognized in accumulated other comprehensive income. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a security that has been in a continuous unrealized/unrecognized loss position for twelve months or longer. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item represents the unrecognized holding gains/losses of a held-to-maturity security that has been in a continuous unrealized/unrecognized loss position for less than twelve months. The unrecognized holding gains/losses represent the market value fluctuations from the later of: (i) the date a security is designated as held-to-maturity; or (ii) the date that an other-than-temporary- impairment charge is recognized on a held-to-maturity security. + References No definition available. + Details
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- Definition This item contains disclosure of the number of available-for-sale and held-to-maturity securities determined to be in an unrealized/unrecognized loss position. + References No definition available. + Details
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- Definition This item represents the percentage decline in fair value of fixed maturity securities compared to amortized cost that have been in a loss position for more than twelve months. This impairment has been determined to be temporary. + References No definition available. + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for twelve months or longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 + Details
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- Definition This item represents the fair value of securities categorized as held-to-maturity that have been in a continuous unrealized loss position for less than twelve months. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563 + Details
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