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Allowance for Credit Losses - Schedule of Held-to-Maturity Debt Securities by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024	Jun. 30, 2024
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Amortized Cost	$ 3,502,584	$ 3,613,720	$ 3,756,415
Less: Allowance for credit losses	(398)	(457)	(491)
Held-to-maturity securities, net of allowance for credit losses	3,502,186	3,613,263	3,755,924
U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	135,000
2021	147,825
Prior	30,715
Amortized Cost	313,540	313,539	336,458
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	147,825
Prior	30,715
Amortized Cost	313,540
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	4,091
2022	1,030
2021	6,767
Prior	144,865
Amortized Cost	156,753	$ 161,016	$ 166,400
Municipal \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	4,091
2022	1,030
2021	6,767
Prior	142,741
Amortized Cost	154,629
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	310,359
2022	508,750
2021	2,159,651
Prior	0
Amortized Cost	2,978,760
Mortgage-backed securities \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	310,359
2022	508,750
2021	2,159,651
Prior	0
Amortized Cost	2,978,760
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	14,971
2021	0
Prior	38,560
Amortized Cost	53,531
Corporate notes \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023
2022	14,971
2021	0
Prior	38,560
Amortized Cost	53,531
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