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Securities - Additional Information (Details)	3 Months Ended	12 Months Ended
	Jun. 30, 2024 USD ($) shares	Dec. 31, 2024 USD ($) Security Segment	Dec. 31, 2023 USD ($) Security	Dec. 31, 2022 USD ($)
Schedule Of Held To Maturity Securities [Line Items]
Number of Investment Securities Segments | Segment		2
Credit losses		$ 0
Municipal securities percentage of securities portfolio		0.90%
Securities in Unrealized Loss Positions Qualitative Disclosure Number of Positions Greater Than or Equal to One Year | Security		949	941
Gain (loss) on sale of investment securities		$ 9,400	$ 0	$ 0
Available for Sale Securities, Amortized Cost Basis		339,016,000	440,358,000
Debt Securities, Available-for-Sale		336,960,000	438,588,000
Collateralized Securities [Member]
Schedule Of Held To Maturity Securities [Line Items]
Available for Sale Securities, Amortized Cost Basis		10,260,000,000	11,340,000,000
Debt Securities, Available-for-Sale		$ 8,910,000,000	$ 10,090,000,000.00
Securities Concentration Risk [Member] | Stockholders' Equity, Total [Member] | Other Than U.S. Government and Agencies [Member]
Schedule Of Held To Maturity Securities [Line Items]
Concentration Risk, Percentage		10.00%	10.00%
Visa Stock Exchange [Member]
Schedule Of Held To Maturity Securities [Line Items]
Conversion of stock, description		During the second quarter of 2024, the Bank tendered all of its shares of Visa, Inc. (“Visa”) Class B-1 common stock in exchange for a combination of Visa Class B-2 common stock and Visa Class C common stock, pursuant to the terms and subject to the conditions of the public offering of Visa to exchange its Class B-1 common stock for a combination of shares of its Class B-2 common stock and Class C common stock, which expired on May 3, 2024.
Gain on stock exchange	$ 20,600,000
Visa Stock Exchange [Member] | Class B-2 Common Stock [Member]
Schedule Of Held To Maturity Securities [Line Items]
Conversion of stock, shares converted | shares	48,492
Cost basis	$ 0
Visa Stock Exchange [Member] | Class C Common Stock [Member]
Schedule Of Held To Maturity Securities [Line Items]
Conversion of stock, shares converted | shares	19,245

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