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Investments (Fair Value and Gross Pre-Tax Net Unrealized Unrecognized Loss of Securities By Length of Time) (Details) - USD ($) $ in Thousands | Jun. 30, 2016 | Dec. 31, 2015
--- | --- | ---
AFS Fair Value, Less than 12 months |  | $ 172,847 | $ 1,449,183
AFS Unrealized Losses, Less than 12 months | [1] | (1,985) | (19,953)
AFS Fair Value, 12 months or longer |  | 98,866 | 141,580
AFS Unrealized Losses, 12 months or longer | [1] | (1,497) | (4,900)
AFS Fixed Income Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 156,419 | 1,416,504
AFS Unrealized Losses, Less than 12 months | [1] | (962) | (17,915)
AFS Fair Value, 12 months or longer |  | 98,866 | 141,580
AFS Unrealized Losses, 12 months or longer | [1] | (1,497) | (4,900)
AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |
AFS Fair Value, Less than 12 months |  |  | 16,006
AFS Unrealized Losses, Less than 12 months | [1] |  | (87)
AFS Fair Value, 12 months or longer |  |  | 396
AFS Unrealized Losses, 12 months or longer | [1] |  | (4)
AFS Fixed Income Securities [Member] | Foreign Government [Member] |  |  |
AFS Fair Value, Less than 12 months |  |  | 1,067
AFS Unrealized Losses, Less than 12 months | [1] |  | (2)
AFS Fair Value, 12 months or longer |  |  | 0
AFS Unrealized Losses, 12 months or longer | [1] |  | 0
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
AFS Fair Value, Less than 12 months |  |  | 28,617
AFS Unrealized Losses, Less than 12 months | [1] |  | (160)
AFS Fair Value, 12 months or longer |  |  | 0
AFS Unrealized Losses, 12 months or longer | [1] |  | 0
AFS Fixed Income Securities [Member] | Corporate Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 96,244 | 761,479
AFS Unrealized Losses, Less than 12 months | [1] | (822) | (12,671)
AFS Fair Value, 12 months or longer |  | 33,616 | 50,382
AFS Unrealized Losses, 12 months or longer | [1] | (1,141) | (2,850)
AFS Fixed Income Securities [Member] | Asset-Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 46,992 | 197,477
AFS Unrealized Losses, Less than 12 months | [1] | (117) | (807)
AFS Fair Value, 12 months or longer |  | 4,665 | 12,022
AFS Unrealized Losses, 12 months or longer | [1] | (10) | (111)
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 6,348 | 146,944
AFS Unrealized Losses, Less than 12 months | [1] | (4) | (2,196)
AFS Fair Value, 12 months or longer |  | 10,451 | 15,385
AFS Unrealized Losses, 12 months or longer | [1] | (47) | (214)
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 6,835 | 264,914
AFS Unrealized Losses, Less than 12 months | [1] | (19) | (1,992)
AFS Fair Value, 12 months or longer |  | 50,134 | 63,395
AFS Unrealized Losses, 12 months or longer | [1] | (299) | (1,721)
Equity Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 16,428 | 32,679
AFS Unrealized Losses, Less than 12 months | [1] | (1,023) | (2,038)
AFS Fair Value, 12 months or longer |  | 0 | 0
AFS Unrealized Losses, 12 months or longer | [1] | 0 | 0
Common Stock [Member] | Equity Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 16,428 | 31,148
AFS Unrealized Losses, Less than 12 months | [1] | (1,023) | (1,998)
AFS Fair Value, 12 months or longer |  | 0 | 0
AFS Unrealized Losses, 12 months or longer | [1] | $ 0 | 0
Preferred Stock [Member] | Equity Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  |  | 1,531
AFS Unrealized Losses, Less than 12 months | [1] |  | (40)
AFS Fair Value, 12 months or longer |  |  | 0
AFS Unrealized Losses, 12 months or longer | [1] |  | $ 0
[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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