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Allowance for Credit Losses - Schedule of Held-to-Maturity Debt Securities by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024	Mar. 31, 2024
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Amortized Cost	$ 3,564,936	$ 3,613,720	$ 3,810,344
Less: Allowance for credit losses	(446)	(457)	(329)
Held-to-maturity securities, net of allowance for credit losses	3,564,490	3,613,263	3,810,015
U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	135,000
2021	147,822
Prior	30,717
Amortized Cost	313,539	313,539	336,463
U.S. government agencies \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	135,000
2021	147,822
Prior	30,717
Amortized Cost	313,539
U.S. government agencies \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
U.S. government agencies \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
Municipal
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	4,176
2022	1,031
2021	6,791
Prior	146,309
Amortized Cost	158,307	$ 161,016	$ 168,490
Municipal \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	4,176
2022	1,031
2021	6,791
Prior	144,185
Amortized Cost	156,183
Municipal \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	2,124
Amortized Cost	2,124
Municipal \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
Mortgage-backed securities
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	323,079
2022	521,866
2021	2,191,464
Prior	0
Amortized Cost	3,036,409
Mortgage-backed securities \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	323,079
2022	521,866
2021	2,191,464
Prior	0
Amortized Cost	3,036,409
Mortgage-backed securities \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
Mortgage-backed securities \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
Corporate notes
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	14,970
2021	0
Prior	41,711
Amortized Cost	56,681
Corporate notes \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	14,970
2021	0
Prior	41,711
Amortized Cost	56,681
Corporate notes \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	0
Corporate notes \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	0
Amortized Cost	$ 0