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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, 2024	Dec. 31, 2023	Jun. 30, 2023
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Amortized Cost	$ 3,756,415	$ 3,857,263	$ 3,564,879
Less: Allowance for credit losses	(491)	(347)	(406)
Held-to-maturity securities, net of allowance for credit losses	3,755,924	3,856,916	3,564,473
U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	156,875
2021	147,815
2020	25,000
Prior	6,768
Amortized Cost	336,458	336,468	339,604
U.S. government agencies \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	156,875
2021	147,815
2020	25,000
Prior	6,768
Amortized Cost	336,458
U.S. government agencies \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
U.S. government agencies \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
Municipal
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	4,176
2022	1,035
2021	6,862
2020	258
Prior	154,069
Amortized Cost	166,400	$ 172,933	$ 176,128
Municipal \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	4,176
2022	1,035
2021	6,862
2020	258
Prior	151,716
Amortized Cost	164,047
Municipal \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	0
2021	0
2020	0
Prior	2,353
Amortized Cost	2,353
Municipal \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
Mortgage-backed securities
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	362,988
2022	555,653
2021	2,277,717
2020	0
Prior	0
Amortized Cost	3,196,358
Mortgage-backed securities \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	362,988
2022	555,653
2021	2,277,717
2020	0
Prior	0
Amortized Cost	3,196,358
Mortgage-backed securities \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
Mortgage-backed securities \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
Corporate notes
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	14,968
2021	0
2020	6,005
Prior	36,226
Amortized Cost	57,199
Corporate notes \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024	0
2023	0
2022	14,968
2021	0
2020	6,005
Prior	36,226
Amortized Cost	57,199
Corporate notes \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	0
Corporate notes \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2024
2023
2022
2021
2020
Prior
Amortized Cost	$ 0