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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, unless otherwise specified | Sep. 30, 2013 | Dec. 31, 2012
--- | --- | ---
AFS Fair Value, Less than 12 months | $ 1,249,722 |  | $ 125,166 |
AFS Unrealized Losses, Less than 12 months | (42,500) | [1] | (1,276) | [1]
AFS Fair Value, 12 months or longer | 11,183 |  | 19,736 |
AFS Unrealized Losses, 12 months or longer | (1,025) | [1] | (1,558) | [1]
HTM Fair Value, Less than 12 months | 492 |  | 1,218 |
HTM Unrealized Losses, Less than 12 months | (20) | [1] | (33) | [1]
HTM Unrecognized Gains, Less than 12 months | 19 | [2] | 29 | [2]
HTM Fair Value, 12 months or longer | 3,047 |  | 3,968 |
HTM Unrealized Losses, 12 months or longer | (714) | [1] | (887) | [1]
HTM Unrecognized Gains, 12 months or longer | 659 | [2] | 791 | [2]
Total AFS and HTM Fair Value, Less than 12 months | 1,250,214 |  | 126,384 |
Total AFS and HTM Unrealized Losses, Less than 12 months | (42,520) | [1] | (1,309) | [1]
Total AFS and HTM Fair Value, 12 months or longer | 14,230 |  | 23,704 |
Total AFS and HTM Unrealized Losses, 12 months or longer | (1,739) | [1] | (2,445) | [1]
Obligations of States and Political Subdivisions [Member] |  |  |  |
HTM Fair Value, Less than 12 months | 492 |  | 1,218 |
HTM Unrealized Losses, Less than 12 months | (20) | [1] | (33) | [1]
HTM Unrecognized Gains, Less than 12 months | 19 | [2] | 29 | [2]
HTM Fair Value, 12 months or longer | 571 |  | 1,108 |
HTM Unrealized Losses, 12 months or longer | (24) | [1] | (47) | [1]
HTM Unrecognized Gains, 12 months or longer | 17 | [2] | 38 | [2]
Asset-backed Securities [Member] |  |  |  |
HTM Fair Value, Less than 12 months | 0 |  | 0 |
HTM Unrealized Losses, Less than 12 months | 0 | [1] | 0 | [1]
HTM Unrecognized Gains, Less than 12 months | 0 | [2] | 0 | [2]
HTM Fair Value, 12 months or longer | 2,476 |  | 2,860 |
HTM Unrealized Losses, 12 months or longer | (690) | [1] | (840) | [1]
HTM Unrecognized Gains, 12 months or longer | 642 | [2] | 753 | [2]
AFS Fixed Maturity Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 1,214,447 |  | 109,265 |
AFS Unrealized Losses, Less than 12 months | (40,622) | [1] | (817) | [1]
AFS Fair Value, 12 months or longer | 11,183 |  | 19,736 |
AFS Unrealized Losses, 12 months or longer | (1,025) | [1] | (1,558) | [1]
AFS Fixed Maturity Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 13,173 |  | 518 |
AFS Unrealized Losses, Less than 12 months | (327) | [1] | (1) | [1]
AFS Fair Value, 12 months or longer | 510 |  | 0 |
AFS Unrealized Losses, 12 months or longer | (3) | [1] | 0 | [1]
AFS Fixed Maturity Securities [Member] | Foreign Government [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 1,056 |  | 0 |
AFS Unrealized Losses, Less than 12 months | (12) | [1] | 0 | [1]
AFS Fair Value, 12 months or longer | 2,925 |  | 2,871 |
AFS Unrealized Losses, 12 months or longer | (72) | [1] | (124) | [1]
AFS Fixed Maturity Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 417,866 |  | 32,383 |
AFS Unrealized Losses, Less than 12 months | (16,610) | [1] | (327) | [1]
AFS Fair Value, 12 months or longer | 0 |  | 0 |
AFS Unrealized Losses, 12 months or longer | 0 | [1] | 0 | [1]
AFS Fixed Maturity Securities [Member] | Corporate Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 422,816 |  | 50,880 |
AFS Unrealized Losses, Less than 12 months | (14,200) | [1] | (402) | [1]
AFS Fair Value, 12 months or longer | 3,837 |  | 0 |
AFS Unrealized Losses, 12 months or longer | (279) | [1] | 0 | [1]
AFS Fixed Maturity Securities [Member] | Asset-backed Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 87,786 |  | 9,137 |
AFS Unrealized Losses, Less than 12 months | (471) | [1] | (9) | [1]
AFS Fair Value, 12 months or longer | 302 |  | 0 |
AFS Unrealized Losses, 12 months or longer | (5) | [1] | 0 | [1]
AFS Fixed Maturity Securities [Member] | Commercial Mortgage-backed Securities (CMBS) [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 69,322 |  | 7,637 |
AFS Unrealized Losses, Less than 12 months | (2,771) | [1] | (19) | [1]
AFS Fair Value, 12 months or longer | 2,030 |  | 11,830 |
AFS Unrealized Losses, 12 months or longer | (492) | [1] | (1,197) | [1]
AFS Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities (RMBS) [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 202,428 |  | 8,710 |
AFS Unrealized Losses, Less than 12 months | (6,231) | [1] | (59) | [1]
AFS Fair Value, 12 months or longer | 1,579 |  | 5,035 |
AFS Unrealized Losses, 12 months or longer | (174) | [1] | (237) | [1]
Equity Securities [Member] |  |  |  |
AFS Fair Value, Less than 12 months | 35,275 |  | 15,901 |
AFS Unrealized Losses, Less than 12 months | (1,878) | [1] | (459) | [1]
AFS Fair Value, 12 months or longer | 0 |  | 0 |
AFS Unrealized Losses, 12 months or longer | $ 0 | [1] | $ 0 | [1]
[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.
[2] | Unrecognized gains represent fair value fluctuations from the later of: (i) the date a security is designated as HTM; or (ii) the date that an OTTI charge is recognized on an HTM security.

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