Securities - Available-for-Sale and Held-to-Maturity by Contractual Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Securities
Securities held-to-maturity, Amortized Cost, Due after ten years	$ 43,039
Securities, held-to-maturity, Amortized Cost, With single maturity date	43,039
Securities, held-to-maturity, Amortized Cost	50,860	$ 51,838
Securities held-to-maturity, Fair Value, Due after ten years	39,196
Securities held-to-maturity, Fair Value, With single maturity date	39,196
Debt Securities, Held-to-maturity, Fair Value, Total	46,384	44,718
Securities available-for-sale, Amortized Cost, Due after one years through five years	70,359
Securities available-for-sale, Amortized Cost, Due after five years through ten years	191,469
Securities available-for-sale, Amortized Cost, Due after ten years	366,665
Securities available-for-sale, Amortized Cost, With single maturity date	628,493
Total Securities available for sale, Amortized Cost	1,541,505	1,506,798
Securities available for sale, Fair Value, Due after one years through five years	69,312
Securities available for sale, Fair Value, Due after five years through ten years	191,305
Securities available for sale, Fair Value, Due after ten years	362,034
Securities available-for-sale, Fair Value, With single maturity date	622,651
Total securities available for sale, Fair Value	1,541,423	1,497,905
Mortgage-backed securities
Securities
Securities held-to-maturity, Amortized Cost, Without single maturity	7,821
Securities held-to-maturity, Fair Value, Without single maturity date	7,188
Securities, available-for-sale, Amortized Cost, Without single maturity date	900,510
Total Securities available for sale, Amortized Cost	900,510	912,870
Securities available-for-sale, Fair Value, Without single maturity date	906,270
Total securities available for sale, Fair Value	906,270	911,636
Mutual funds
Securities
Securities, available-for-sale, Amortized Cost, Without single maturity date	12,502
Total Securities available for sale, Amortized Cost	12,502	11,890
Securities available-for-sale, Fair Value, Without single maturity date	12,502
Total securities available for sale, Fair Value	$ 12,502	$ 11,890

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