Allowance for Credit Losses - Schedule of Held-to-Maturity Debt Securities by Credit Quality Indicator (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
Amortized Cost	$ 3,857,263	$ 3,641,055
Less: Allowance for credit losses	(347)	(488)
Held-to-maturity securities, net of allowance for credit losses	3,856,916	3,640,567
U.S. government agencies
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	156,875
2021	147,810
2020	25,000
2019	4,000
Prior	2,783
Amortized Cost	336,468	339,614
U.S. government agencies \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	156,875
2021	147,810
2020	25,000
2019	4,000
Prior	2,783
Amortized Cost	336,468
U.S. government agencies \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
U.S. government agencies \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Municipal
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	4,176
2022	1,038
2021	6,909
2020	259
2019	611
Prior	159,940
Amortized Cost	172,933	$ 179,027
Municipal \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	4,176
2022	1,038
2021	6,909
2020	259
2019	611
Prior	159,940
Amortized Cost	172,933
Municipal \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Municipal \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Mortgage-backed securities
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	382,825
2022	574,935
2021	2,332,558
2020	0
2019	0
Prior	0
Amortized Cost	3,290,318
Mortgage-backed securities \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	382,825
2022	574,935
2021	2,332,558
2020	0
2019	0
Prior	0
Amortized Cost	3,290,318
Mortgage-backed securities \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Mortgage-backed securities \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Corporate notes
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	14,966
2021	0
2020	6,007
2019	7,226
Prior	29,345
Amortized Cost	57,544
Corporate notes \| 1-4 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	14,966
2021	0
2020	6,007
2019	7,226
Prior	29,345
Amortized Cost	57,544
Corporate notes \| 5-7 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	0
Prior	0
Amortized Cost	0
Corporate notes \| 8-10 internal grade
Debt Securities, Held-to-maturity, Credit Quality Indicator [Line Items]
2023	0
2022	0
2021	0
2020	0
2019	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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