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Real Estate Owned, Net - Additional Information (Detail) $ in Thousands	3 Months Ended						9 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($) real_estate_owned_asset	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($)	Mar. 31, 2024 USD ($)	Sep. 30, 2025 USD ($) real_estate_owned_asset	Dec. 31, 2024 USD ($) real_estate_owned_asset
Real Estate [Line Items]
Number of REO assets classified as held for sale investment | real_estate_owned_asset	10						10	7
Number of real estate owned assets | real_estate_owned_asset							3
Total acquisition price							$ 406,300
Land and land improvements	$ 221,000						221,000
Building and building improvements	137,100						137,100
Acquired intangible assets	49,200						49,200
Other components	(1,000)						(1,000)
Amount charged off	42,111	$ 45,057	$ 41,824	$ 16,989	$ 12,537	$ 61,013	128,992	$ 384,603
Real estate owned, net	933,635						933,635	$ 588,185
7 Real Estate Owned Assets
Real Estate [Line Items]
Real estate owned, net	$ 490,200						490,200
Commercial Real Estate
Real Estate [Line Items]
Amount charged off							$ 83,900

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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
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Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
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