Allowance for Credit Losses - Schedule of Held-to-Maturity Debt Securities by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Amortized Cost	$ 3,344,165	$ 3,613,720
Less: Allowance for credit losses	(260)	(457)
Held-to-maturity securities, net of allowance for credit losses	3,343,905	3,613,263
U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	135,000
2021	147,830
Prior	30,711
Amortized Cost	313,541	313,539
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	147,830
Prior	30,711
Amortized Cost	313,541
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	4,092
2022	1,027
2021	6,718
Prior	132,355
Amortized Cost	144,192	$ 161,016
Municipal \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	4,092
2022	1,027
2021	6,718
Prior	130,468
Amortized Cost	142,305
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	1,887
Amortized Cost	1,887
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	273,577
2022	480,317
2021	2,097,441
Prior	0
Amortized Cost	2,851,335
Mortgage-backed securities \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	273,577
2022	480,317
2021	2,097,441
Prior	0
Amortized Cost	2,851,335
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	4,973
2021	0
Prior	30,124
Amortized Cost	35,097
Corporate notes \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2025	0
2024	0
2023	0
2022	4,973
2021	0
Prior	30,124
Amortized Cost	35,097
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

Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity).

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