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Number of mortgage loans within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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Value of input used to measure alternative investment.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Fair Value Disclosures - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2026 USD ($) Loans	Jun. 30, 2025 USD ($) Loans	Jun. 30, 2026 USD ($) Loans	Jun. 30, 2025 USD ($) Loans	Dec. 31, 2025 USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets transfer between Level 2 and Level 3	$ 0	$ 0	$ 0	$ 0
Other real estate owned, total	$ 2,763,000		$ 2,763,000		$ 280,000
Residential Mortgage [Member] \| Greater than 90 Days [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Number of loans held-for-sale \| Loans	0	0	0	0
Recognized credit losses	$ 0	$ 0	$ 0	$ 0
Minimum [Member] \| Measurement Input, Discount Rate [Member] \| Greater than 90 Days [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt discounts, percentage	5		5
Maximum [Member] \| Measurement Input, Discount Rate [Member] \| Greater than 90 Days [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt discounts, percentage	25		25