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Securities - Gross Unrealized Losses and Fair Value by Investment Category (Details) $ in Thousands | Jun. 30, 2023 USD ($) security | Dec. 31, 2022 USD ($) security
--- | --- | ---
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 18 | 247
Fair Value, Less than 12 Months | $ 21,123 | $ 726,431
Unrealized Losses, Less than 12 Months | $ (1,241) | $ (41,924)
Number of positions, 12 Months or More | security | 143 | 98
Fair value, 12 Months or More | $ 889,083 | $ 788,657
Unrealized Losses, 12 Months or More | $ (178,308) | $ (159,375)
Number of positions | security | 161 | 345
Fair Value | $ 910,206 | $ 1,515,088
Unrealized Losses | $ (179,549) | $ (201,299)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 130 | 122
Fair Value, Less than 12 Months | $ 312,387 | $ 448,575
Unrealized Losses, Less than 12 Months | $ (45,730) | $ (51,436)
Number of positions, 12 Months or More | security | 105 | 115
Fair Value, 12 Months or More | $ 837,063 | $ 755,527
Unrealized Losses, 12 Months or More | $ (73,828) | $ (66,113)
Number of positions | security | 235 | 237
Fair Value | $ 1,149,450 | $ 1,204,102
Unrealized Losses | $ (119,558) | $ (117,549)
Obligations of other U.S. Government agencies and corporations |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security |  | 5
Fair Value, Less than 12 Months |  | $ 164,660
Unrealized Losses, Less than 12 Months |  | $ (5,340)
Number of positions, 12 Months or More | security |  | 0
Fair value, 12 Months or More |  | $ 0
Unrealized Losses, 12 Months or More |  | $ 0
Number of positions | security |  | 5
Fair Value |  | $ 164,660
Unrealized Losses |  | $ (5,340)
Obligations of states and political subdivisions |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 10 | 84
Fair Value, Less than 12 Months | $ 7,827 | $ 96,939
Unrealized Losses, Less than 12 Months | $ (35) | $ (4,869)
Number of positions, 12 Months or More | security | 10 | 11
Fair value, 12 Months or More | $ 23,073 | $ 33,038
Unrealized Losses, 12 Months or More | $ (3,404) | $ (4,499)
Number of positions | security | 20 | 95
Fair Value | $ 30,900 | $ 129,977
Unrealized Losses | $ (3,439) | $ (9,368)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 126 | 105
Fair Value, Less than 12 Months | $ 242,673 | $ 191,442
Unrealized Losses, Less than 12 Months | $ (42,767) | $ (35,871)
Number of positions, 12 Months or More | security | 1 | 24
Fair Value, 12 Months or More | $ 426 | $ 49,697
Unrealized Losses, 12 Months or More | $ (15) | $ (12,454)
Number of positions | security | 127 | 129
Fair Value | $ 243,099 | $ 241,139
Unrealized Losses | $ (42,782) | $ (48,325)
Other debt securities |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 3 | 25
Fair Value, Less than 12 Months | $ 5,492 | $ 63,423
Unrealized Losses, Less than 12 Months | $ (800) | $ (3,167)
Number of positions, 12 Months or More | security | 18 | 1
Fair value, 12 Months or More | $ 32,171 | $ 7,412
Unrealized Losses, 12 Months or More | $ (4,869) | $ (883)
Number of positions | security | 21 | 26
Fair Value | $ 37,663 | $ 70,835
Unrealized Losses | $ (5,669) | $ (4,050)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 0 | 2
Fair Value, Less than 12 Months | $ 0 | $ 42,567
Unrealized Losses, Less than 12 Months | $ 0 | $ (2,013)
Number of positions, 12 Months or More | security | 10 | 8
Fair Value, 12 Months or More | $ 50,323 | $ 16,042
Unrealized Losses, 12 Months or More | $ (5,058) | $ (2,253)
Number of positions | security | 10 | 10
Fair Value | $ 50,323 | $ 58,609
Unrealized Losses | $ (5,058) | $ (4,266)
Government agency mortgage backed securities | Residential mortgage backed securities: |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 4 | 97
Fair Value, Less than 12 Months | $ 6,673 | $ 214,516
Unrealized Losses, Less than 12 Months | $ (368) | $ (15,115)
Number of positions, 12 Months or More | security | 46 | 29
Fair value, 12 Months or More | $ 275,823 | $ 237,970
Unrealized Losses, 12 Months or More | $ (42,383) | $ (36,921)
Number of positions | security | 50 | 126
Fair Value | $ 282,496 | $ 452,486
Unrealized Losses | $ (42,751) | $ (52,036)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 2 | 8
Fair Value, Less than 12 Months | $ 39,028 | $ 94,258
Unrealized Losses, Less than 12 Months | $ (1,387) | $ (4,186)
Number of positions, 12 Months or More | security | 68 | 62
Fair Value, 12 Months or More | $ 395,220 | $ 364,870
Unrealized Losses, 12 Months or More | $ (24,410) | $ (20,246)
Number of positions | security | 70 | 70
Fair Value | $ 434,248 | $ 459,128
Unrealized Losses | $ (25,797) | $ (24,432)
Government agency mortgage backed securities | Commercial mortgage backed securities: |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 0 | 4
Fair Value, Less than 12 Months | $ 0 | $ 10,114
Unrealized Losses, Less than 12 Months | $ 0 | $ (1,053)
Number of positions, 12 Months or More | security | 2 | 0
Fair value, 12 Months or More | $ 5,245 | $ 0
Unrealized Losses, 12 Months or More | $ (797) | $ 0
Number of positions | security | 2 | 4
Fair Value | $ 5,245 | $ 10,114
Unrealized Losses | $ (797) | $ (1,053)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 0 | 1
Fair Value, Less than 12 Months | $ 0 | $ 13,745
Unrealized Losses, Less than 12 Months | $ 0 | $ (3,261)
Number of positions, 12 Months or More | security | 1 | 0
Fair Value, 12 Months or More | $ 13,764 | $ 0
Unrealized Losses, 12 Months or More | $ (3,231) | $ 0
Number of positions | security | 1 | 1
Fair Value | $ 13,764 | $ 13,745
Unrealized Losses | $ (3,231) | $ (3,261)
Government agency collateralized mortgage obligations | Residential mortgage backed securities: |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 0 | 16
Fair Value, Less than 12 Months | $ 0 | $ 109,753
Unrealized Losses, Less than 12 Months | $ 0 | $ (8,552)
Number of positions, 12 Months or More | security | 41 | 36
Fair value, 12 Months or More | $ 415,090 | $ 391,416
Unrealized Losses, 12 Months or More | $ (101,385) | $ (95,312)
Number of positions | security | 41 | 52
Fair Value | $ 415,090 | $ 501,169
Unrealized Losses | $ (101,385) | $ (103,864)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 1 | 4
Fair Value, Less than 12 Months | $ 26,396 | $ 98,912
Unrealized Losses, Less than 12 Months | $ (1,278) | $ (5,479)
Number of positions, 12 Months or More | security | 17 | 14
Fair Value, 12 Months or More | $ 344,025 | $ 293,698
Unrealized Losses, 12 Months or More | $ (34,094) | $ (25,227)
Number of positions | security | 18 | 18
Fair Value | $ 370,421 | $ 392,610
Unrealized Losses | $ (35,372) | $ (30,706)
Government agency collateralized mortgage obligations | Commercial mortgage backed securities: |  |
Available for Sale: |  |
Number of positions, Less than 12 Months | security | 1 | 16
Fair Value, Less than 12 Months | $ 1,131 | $ 67,026
Unrealized Losses, Less than 12 Months | $ (38) | $ (3,828)
Number of positions, 12 Months or More | security | 26 | 21
Fair value, 12 Months or More | $ 137,681 | $ 118,821
Unrealized Losses, 12 Months or More | $ (25,470) | $ (21,760)
Number of positions | security | 27 | 37
Fair Value | $ 138,812 | $ 185,847
Unrealized Losses | $ (25,508) | $ (25,588)
Held to Maturity: |  |
Number of positions, Less than 12 Months | security | 1 | 2
Fair Value, Less than 12 Months | $ 4,290 | $ 7,651
Unrealized Losses, Less than 12 Months | $ (298) | $ (626)
Number of positions, 12 Months or More | security | 8 | 7
Fair Value, 12 Months or More | $ 33,305 | $ 31,220
Unrealized Losses, 12 Months or More | $ (7,020) | $ (5,933)
Number of positions | security | 9 | 9
Fair Value | $ 37,595 | $ 38,871
Unrealized Losses | $ (7,318) | $ (6,559)

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