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Investments (Fair Value and Gross Pre-Tax Net Unrealized Loss of Securities By Length of Time) (Details) - Available-for-sale Securities - USD ($) $ in Thousands | Jun. 30, 2021 | Dec. 31, 2020
--- | --- | ---
AFS Fair Value, Less than 12 Months | $ 666,285 | $ 415,506
AFS Unrealized Losses, Less than 12 months | (4,864) | (6,108)
AFS Fair Value, 12 months or longer | 91,800 | 185,335
AFS Unrealized Losses, 12 months or longer | (1,861) | (5,434)
AFS Fair Value | 758,085 | 600,841
AFS Unrealized Losses | (6,725) | (11,542)
U.S. Government and Government Agencies [Member] |  |
AFS Fair Value, Less than 12 Months | 17,582 | 11,519
AFS Unrealized Losses, Less than 12 months | (631) | (137)
AFS Fair Value, 12 months or longer | 0 | 0
AFS Unrealized Losses, 12 months or longer | 0 | 0
AFS Fair Value | 17,582 | 11,519
AFS Unrealized Losses | (631) | (137)
Foreign Government [Member] |  |
AFS Fair Value, Less than 12 Months | 3,122 | 1,122
AFS Unrealized Losses, Less than 12 months | (73) | (3)
AFS Fair Value, 12 months or longer | 0 | 0
AFS Unrealized Losses, 12 months or longer | 0 | 0
AFS Fair Value | 3,122 | 1,122
AFS Unrealized Losses | (73) | (3)
Obligations of States and Political Subdivisions [Member] |  |
AFS Fair Value, Less than 12 Months | 7,222 | 2,223
AFS Unrealized Losses, Less than 12 months | (103) | (11)
AFS Fair Value, 12 months or longer | 0 | 0
AFS Unrealized Losses, 12 months or longer | 0 | 0
AFS Fair Value | 7,222 | 2,223
AFS Unrealized Losses | (103) | (11)
Corporate Securities [Member] |  |
AFS Fair Value, Less than 12 Months | 84,676 | 65,187
AFS Unrealized Losses, Less than 12 months | (880) | (2,152)
AFS Fair Value, 12 months or longer | 6,163 | 2,400
AFS Unrealized Losses, 12 months or longer | (675) | (188)
AFS Fair Value | 90,839 | 67,587
AFS Unrealized Losses | (1,555) | (2,340)
Collateralized Loan Obligations and Other Asset Backed Securities [Member] |  |
AFS Fair Value, Less than 12 Months | 415,284 | 261,746
AFS Unrealized Losses, Less than 12 months | (1,699) | (2,995)
AFS Fair Value, 12 months or longer | 71,126 | 165,661
AFS Unrealized Losses, 12 months or longer | (1,025) | (4,848)
AFS Fair Value | 486,410 | 427,407
AFS Unrealized Losses | (2,724) | (7,843)
Residential Mortgage Backed Securities [Member] |  |
AFS Fair Value, Less than 12 Months | 84,141 | 18,227
AFS Unrealized Losses, Less than 12 months | (774) | (194)
AFS Fair Value, 12 months or longer | 0 | 1,181
AFS Unrealized Losses, 12 months or longer | 0 | (7)
AFS Fair Value | 84,141 | 19,408
AFS Unrealized Losses | (774) | (201)
Commercial Mortgage Backed Securities [Member] |  |
AFS Fair Value, Less than 12 Months | 54,258 | 55,482
AFS Unrealized Losses, Less than 12 months | (704) | (616)
AFS Fair Value, 12 months or longer | 14,511 | 16,093
AFS Unrealized Losses, 12 months or longer | (161) | (391)
AFS Fair Value | 68,769 | 71,575
AFS Unrealized Losses | $ (865) | $ (1,007)

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