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Investment Securities - Schedule of Unrealized Losses and Estimated Fair Values (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | $ 15,380 | $ 376,595
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (111) | (37,023)
Estimated Fair Value, 12 Months or More | 1,018,290 | 763,274
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (193,924) | (174,250)
Securities Continuous Unrealized Loss Position Fair Value | 1,033,670 | 1,139,869
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (194,035) | (211,273)
US States and Political Subdivisions Debt Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 2,641 | 21,234
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (62) | (1,979)
Estimated Fair Value, 12 Months or More | 26,887 | 9,230
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (3,377) | (2,181)
Securities Continuous Unrealized Loss Position Fair Value | 29,528 | 30,464
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (3,439) | (4,160)
ERROR in label resolution. |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 199 |
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (1) |
Estimated Fair Value, 12 Months or More | 765 |
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (35) |
Securities Continuous Unrealized Loss Position Fair Value | 964 |
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (36) |
Corporate Securities [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 11,416 | 14,406
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (45) | (590)
Estimated Fair Value, 12 Months or More | 21,426 | 12,632
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (3,574) | (2,395)
Securities Continuous Unrealized Loss Position Fair Value | 32,842 | 27,038
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (3,619) | (2,985)
Foreign Government Debt |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months |  | 587
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses |  | (13)
Estimated Fair Value, 12 Months or More |  | 373
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses |  | (27)
Securities Continuous Unrealized Loss Position Fair Value |  | 960
SecuritiesContinuousUnrealizedLossPositionAggregateLosses |  | (40)
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 0 | 3,734
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | 0 | (405)
Estimated Fair Value, 12 Months or More | 3,395 | 0
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (322) | 0
Securities Continuous Unrealized Loss Position Fair Value | 3,395 | 3,734
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (322) | (405)
Mortgage - Backed Securities - Residential [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 1,124 | 239,760
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | (3) | (21,543)
Estimated Fair Value, 12 Months or More | 643,735 | 482,195
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (115,367) | (110,306)
Securities Continuous Unrealized Loss Position Fair Value | 644,859 | 721,955
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (115,370) | (131,849)
Mortgage - Backed Securities - Commercial [Member] | Obligations of U.S. Government [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 0 | 92,208
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | 0 | (12,364)
Estimated Fair Value, 12 Months or More | 300,642 | 240,241
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (66,956) | (54,722)
Securities Continuous Unrealized Loss Position Fair Value | 300,642 | 332,449
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (66,956) | (67,086)
Mortgage - Backed Securities - Commercial [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 0 | 4,666
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | 0 | (129)
Estimated Fair Value, 12 Months or More | 2,160 | 0
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (30) | 0
Securities Continuous Unrealized Loss Position Fair Value | 2,160 | 4,666
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | (30) | (129)
Other Government - Sponsored Enterprises [Member] | Obligations of U.S. Government-Sponsored Enterprises [Member] |  |
Debt Securities, Available-for-sale, Unrealized Loss Position [Line Items] |  |
Estimated Fair Value, Less Than 12 Months | 0 | 0
Available For Sale Securities Continuous Unrealized Income Loss Position Less Than Twelve Months Aggregate Gain Losses | 0 | 0
Estimated Fair Value, 12 Months or More | 19,280 | 18,603
SecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAggregateLosses | (4,263) | (4,619)
Securities Continuous Unrealized Loss Position Fair Value | 19,280 | 18,603
SecuritiesContinuousUnrealizedLossPositionAggregateLosses | $ (4,263) | $ (4,619)

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