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Investments (Number of Securities in an Unrealized Unrecognized Loss Position) (Details) $ in Thousands | Dec. 31, 2016 USD ($) Securities | Dec. 31, 2015 USD ($) Securities
--- | --- | ---
Unrealized Unrecognized Loss | $ 16,215 | $ 24,859
Percentage Decline in Fair Value Percentage | 1.00% |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | $ 1,358,111 | 1,449,183
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (15,651) | (19,953)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 15,626 | 141,580
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (406) | (4,900)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 1,373,737 | 1,590,763
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | $ (16,057) | $ (24,853)
Eighty Percent to Ninety-Nine Percent [Member] |  |
Number of securities in an unrealized/unrecognized loss position | Securities | 456 | 606
Unrealized Unrecognized Loss | $ 16,215 | $ 22,971
Sixty Percent to Seventy-Nine Percent [Member] |  |
Number of securities in an unrealized/unrecognized loss position | Securities | 0 | 3
Unrealized Unrecognized Loss | $ 0 | $ 1,888
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, Less than Twelve Months, Fair Value | 1,340,672 | 1,416,504
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (14,991) | (17,915)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 15,626 | 141,580
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (406) | (4,900)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 1,356,298 | 1,558,084
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (15,397) | (22,815)
Equity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 17,439 | 32,679
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (660) | (2,038)
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, Fair Value | 17,439 | 32,679
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (660) | (2,038)
U.S. Government and Government Agencies [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 6,419 | 16,006
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (36) | (87)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 0 | 396
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | 0 | (4)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 6,419 | 16,402
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (36) | (91)
Foreign Government [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 13,075 | 1,067
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (16) | (2)
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, Fair Value | 13,075 | 1,067
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (16) | (2)
Obligations of States and Political Subdivisions [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 306,509 | 28,617
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (5,304) | (160)
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, Fair Value | 306,509 | 28,617
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (5,304) | (160)
Corporate Securities [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 462,902 | 761,479
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (5,771) | (12,671)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 4,913 | 50,382
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (89) | (2,850)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 467,815 | 811,861
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (5,860) | (15,521)
Collateralized Loan Obligations and Other Asset-Backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 189,795 | 197,477
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (354) | (807)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 319 | 12,022
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (1) | (111)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 190,114 | 209,499
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (355) | (918)
Commercial Mortgage Backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 82,492 | 146,944
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (1,021) | (2,196)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 1,645 | 15,385
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (7) | (214)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 84,137 | 162,329
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (1,028) | (2,410)
Residential Mortgage Backed Securities [Member] | Afs Fixed Maturity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 279,480 | 264,914
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (2,489) | (1,992)
Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value | 8,749 | 63,395
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss | (309) | (1,721)
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value | 288,229 | 328,309
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (2,798) | (3,713)
Common Stock [Member] | Equity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 11,271 | 31,148
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (305) | (1,998)
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, Fair Value | 11,271 | 31,148
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | (305) | (1,998)
Nonredeemable Preferred Stock [Member] | Equity Securities [Member] |  |
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value | 6,168 | 1,531
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss | (355) | (40)
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, Fair Value | 6,168 | 1,531
Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss | $ (355) | $ (40)

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- Definition This item represents the sum of (i) the excess of amortized cost over fair value for available-for-sale securities that are in a loss position and (ii) the market fluctuations on held-to-maturity securities from the later of (a) the date a security is designated as held-to-maturity; or (b) the date that an other-than-temporary impairment charge is recognized on a held-to-maturity security for securities that are in an unrecognized loss position. + 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=73527792&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=73527792&loc=d3e27337-111563 + Details
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