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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 | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
AFS Fair Value, Less than 12 months |  | $ 879,619 | $ 466,387
AFS Unrealized Losses, Less than 12 months | [1] | (21,084) | (2,408)
AFS Fair Value, 12 months or longer |  | 144,459 | 442,058
AFS Unrealized Losses, 12 months or longer | [1] | (2,760) | (8,170)
HTM Fair Value, Less than 12 months |  | 0 | 196
HTM Unrealized Losses, Less than 12 months | [1] | 0 | (3)
HTM Unrecognized Gains, Less than 12 months | [2] | 0 | 1
HTM Fair Value, 12 months or longer |  | 942 | 2,235
HTM Unrealized Losses, 12 months or longer | [1] | (157) | (455)
HTM Unrecognized Gains, 12 months or longer | [2] | 153 | 439
Total AFS and HTM Fair Value, Less than 12 months |  | 879,619 | 466,583
Total AFS and HTM Unrealized Losses, Less than 12 months | [1] | (21,084) | (2,411)
Total AFS and HTM Securities Unrecognized Gains, Less Than 12 Months | [2] | 0 | 1
Total AFS and HTM Fair Value, 12 months or longer |  | 145,401 | 444,293
Total AFS and HTM Unrealized Losses, 12 months or longer | [1] | (2,917) | (8,625)
Total AFS and HTM Securities Unrecognized Gains, 12 months or longer | [2] | 153 | 439
Obligations of States and Political Subdivisions [Member] |  |  |
HTM Fair Value, Less than 12 months |  |  | 196
HTM Unrealized Losses, Less than 12 months | [1] |  | (3)
HTM Unrecognized Gains, Less than 12 months | [2] |  | 1
HTM Fair Value, 12 months or longer |  |  | 0
HTM Unrealized Losses, 12 months or longer | [1] |  | 0
HTM Unrecognized Gains, 12 months or longer | [2] |  | 0
Asset-Backed Securities [Member] |  |  |
HTM Fair Value, Less than 12 months |  | 0 | 0
HTM Unrealized Losses, Less than 12 months | [1] | 0 | 0
HTM Unrecognized Gains, Less than 12 months | [2] | 0 | 0
HTM Fair Value, 12 months or longer |  | 942 | 2,235
HTM Unrealized Losses, 12 months or longer | [1] | (157) | (455)
HTM Unrecognized Gains, 12 months or longer | [2] | 153 | 439
AFS Fixed Income Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 737,456 | 461,125
AFS Unrealized Losses, Less than 12 months | [1] | (8,627) | (2,072)
AFS Fair Value, 12 months or longer |  | 144,459 | 442,058
AFS Unrealized Losses, 12 months or longer | [1] | (2,760) | (8,170)
AFS Fixed Income Securities [Member] | U.S. Government and Government Agencies [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 0 | 7,567
AFS Unrealized Losses, Less than 12 months | [1] | 0 | (13)
AFS Fair Value, 12 months or longer |  | 399 | 10,866
AFS Unrealized Losses, 12 months or longer | [1] | (1) | (115)
AFS Fixed Income Securities [Member] | Obligations of States and Political Subdivisions [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 96,861 | 47,510
AFS Unrealized Losses, Less than 12 months | [1] | (545) | (105)
AFS Fair Value, 12 months or longer |  | 0 | 64,018
AFS Unrealized Losses, 12 months or longer | [1] | 0 | (624)
AFS Fixed Income Securities [Member] | Corporate Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 430,481 | 276,648
AFS Unrealized Losses, Less than 12 months | [1] | (7,187) | (1,734)
AFS Fair Value, 12 months or longer |  | 50,552 | 153,613
AFS Unrealized Losses, 12 months or longer | [1] | (1,695) | (4,075)
AFS Fixed Income Securities [Member] | Asset-Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 55,856 | 113,202
AFS Unrealized Losses, Less than 12 months | [1] | (71) | (178)
AFS Fair Value, 12 months or longer |  | 12,530 | 15,618
AFS Unrealized Losses, 12 months or longer | [1] | (34) | (195)
AFS Fixed Income Securities [Member] | Commercial Mortgage Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 59,004 | 12,799
AFS Unrealized Losses, Less than 12 months | [1] | (367) | (34)
AFS Fair Value, 12 months or longer |  | 15,561 | 59,219
AFS Unrealized Losses, 12 months or longer | [1] | (90) | (743)
AFS Fixed Income Securities [Member] | Residential Mortgage Backed Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 95,254 | 3,399
AFS Unrealized Losses, Less than 12 months | [1] | (457) | (8)
AFS Fair Value, 12 months or longer |  | 65,417 | 138,724
AFS Unrealized Losses, 12 months or longer | [1] | (940) | (2,418)
Equity Securities [Member] |  |  |
AFS Fair Value, Less than 12 months |  | 142,163 | 5,262
AFS Unrealized Losses, Less than 12 months | [1] | (12,457) | (336)
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 |  | 133,601 | 5,262
AFS Unrealized Losses, Less than 12 months | [1] | (12,340) | (336)
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 |  | 8,562 |
AFS Unrealized Losses, Less than 12 months | [1] | (117) |
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.
[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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