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- Definition

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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- Definition

Value of input used to measure alternative investment.

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- Definition

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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- Definition

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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Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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Fair Value Disclosures - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2026 USD ($) Loans	Mar. 31, 2025 USD ($) 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
Other real estate owned, total	1,845,000		$ 280,000
Greater than 90 Days [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Real state owned	$ 0	$ 0
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
Recognized credit losses	$ 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
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