Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)		3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 01, 2025	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024	Dec. 31, 2024	Dec. 31, 2021
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest-bearing funds deposited in other banks		$ 800,000		$ 800,000
Non-marketable securities		8,100,000		8,100,000		$ 9,200,000
Impact of equity investment		6,300,000		6,300,000
Notes receivable net		93,083,000		93,083,000		2,444,376,000
Equity securities, fair value		1,800,000		1,800,000		1,700,000
Gains (Loss) on Equity Securities		100,000	$ (100,000)	100,000	$ (100,000)
Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest		0		0		0
Purchased of equity securities with readily determinable fair value							$ 2,000,000
Investment, Type [Extensible Enumeration]							us-gaap:EquitySecuritiesMember
Net loan origination costs				47,600,000		46,600,000
Net Amortization to income		2,600,000	2,300,000	4,900,000	4,300,000
Fair value adjustments related to loans held for sale				0		0
Goodwill		150,803,000		150,803,000		150,803,000
Intangible assets, net		18,424,000		18,424,000		19,146,000
Amortization of intangible assets		362,000	362,000	723,000	723,000
Depreciation and amortization		600,000	100,000	1,200,000	200,000
Amortization expense		1,100,000	900,000	2,200,000	$ 1,800,000
Deferred costs		$ 8,500,000		$ 8,500,000		$ 8,200,000
Potential dilutive common shares excluded from EPS computation				86,410	101,350
Tier 1 leverage capital to total assets ratio		15.00%		15.00%
Excess Tier 1 leverage capital		$ 106,900,000		$ 106,900,000
Tier 1 leverage capital		372,800,000		$ 372,800,000
Capital conversation buffer				2.50%		2.50%
Equity Investments [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Impairments on Equity Investments		400,000	500,000	$ 900,000	$ 800,000
Disposition and Exit of Equity Investments [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gains (Loss) on Equity Securities		6,100,000	$ (500,000)	15,500,000	$ 3,700,000
Series F Preferred Stock | Subsequent Event
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Redemption price of stock	$ 46,000,000
New York Taxi Medallion [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Notes receivable net		$ 79,500		79,500
Medallion Bank [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Amortization of intangible assets				$ 0		$ 0
Minimum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest bearing loan term				5 years
Estimated useful life of fixed assets		3 years		3 years
Maximum [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Interest bearing loan term				6 years
Estimated useful life of fixed assets		10 years		10 years