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Amount of contractual principal due at origination of mortgage loan 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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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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-Topic 460
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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Value of input used to measure loan, held for sale.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Summary of Significant Accounting Policies (Details)	6 Months Ended				12 Months Ended
Summary of Significant Accounting Policies (Details)	Jun. 30, 2026 USD ($) real_estate_owned_asset	Jun. 30, 2026 USD ($) loan real_estate_owned_asset	Jun. 30, 2026 USD ($) real_estate_owned_asset security_loan	Jun. 30, 2026 USD ($) real_estate_owned_asset	Dec. 31, 2025 USD ($) real_estate_owned_asset portfolio	Dec. 31, 2025 USD ($) loan real_estate_owned_asset	Dec. 31, 2025 USD ($) real_estate_owned_asset security_loan	Mar. 31, 2026 USD ($)	Sep. 30, 2025 USD ($)	Jun. 30, 2025 USD ($)	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Restricted cash	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0
Number of REO assets classified as held for sale investment \| real_estate_owned_asset	14	14	14	14	12	12	12
Maximum guarantee	$ 5,500,000	$ 5,500,000	$ 5,500,000	$ 5,500,000	$ 5,500,000	$ 5,500,000	$ 5,500,000
Guarantee liability	32,000	32,000	32,000	32,000	32,000	32,000	32,000
CECL reserve	397,835,000	$ 397,835,000	$ 397,835,000	397,835,000	284,440,000	$ 284,440,000	$ 284,440,000	$ 291,590,000		$ 740,851,000	$ 741,541,000	$ 733,936,000
Number of loans		133	133			131	131
Principal balance	17,334,730,000	$ 17,334,730,000	$ 17,334,730,000	17,334,730,000	$ 18,069,134,000	$ 18,069,134,000	$ 18,069,134,000
Related Party
Accounts, Notes, Loans and Financing Receivable [Line Items]
Face amount of loans	$ 286,700,000	$ 286,700,000	$ 286,700,000	$ 286,700,000					$ 606,000,000.0	$ 1,400,000,000
Two Property Through Foreclosure
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of real estate owned assets \| real_estate_owned_asset				2
Level 3 \| Minimum \| Capitalization rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Measurement input	0.049	0.049	0.049	0.049
Level 3 \| Minimum \| Discount rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Measurement input	0.093	0.093	0.093	0.093
Level 3 \| Maximum \| Capitalization rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Measurement input	0.085	0.085	0.085	0.085
Level 3 \| Maximum \| Discount rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Measurement input	0.150	0.150	0.150	0.150
Level 3 \| Fair Value, Nonrecurring
Accounts, Notes, Loans and Financing Receivable [Line Items]
CECL reserve	$ 219,500,000	$ 219,500,000	$ 219,500,000	$ 219,500,000
Number of loans \| loan		9
Principal balance	$ 695,200,000	$ 695,200,000	$ 695,200,000	$ 695,200,000
Level 3 \| Fair Value, Nonrecurring \| Minimum \| Capitalization rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate owned, measurement input	0.058	0.058	0.058	0.058
Level 3 \| Fair Value, Nonrecurring \| Minimum \| Discount rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate owned, measurement input	0.080	0.080	0.080	0.080
Level 3 \| Fair Value, Nonrecurring \| Maximum \| Capitalization rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate owned, measurement input	0.065	0.065	0.065	0.065
Level 3 \| Fair Value, Nonrecurring \| Maximum \| Discount rate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Real estate owned, measurement input	0.110	0.110	0.110	0.110
Building
Accounts, Notes, Loans and Financing Receivable [Line Items]
Estimated useful lives (in years)	40 years
Land Improvements
Accounts, Notes, Loans and Financing Receivable [Line Items]
Estimated useful lives (in years)	15 years
Leasehold Improvements
Accounts, Notes, Loans and Financing Receivable [Line Items]
Estimated useful lives (in years)	10 years
Bank Loan Portfolio Joint Venture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Ownership percentage	35.00%	35.00%	35.00%	35.00%	35.00%	35.00%	35.00%
Number of loan portfolio acquired \| portfolio					2
Homebuilder Finance Joint Venture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Ownership percentage	45.00%	45.00%	45.00%	45.00%
Net Lease Joint Venture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Ownership percentage	75.00%	75.00%	75.00%	75.00%	75.00%	75.00%	75.00%
Multifamily Joint Venture
Accounts, Notes, Loans and Financing Receivable [Line Items]
Ownership percentage													85.00%
Multifamily Joint Venture \| Walker & Dunlop
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minority participation in senior term facility													15.00%