Fair Value Measurements - Schedule of Financial Instruments Measured at Carrying And Estimated Fair Value (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans receivable held-for-investment, net	$ 6,340,295	$ 6,125,825
Interests in loans receivable held-for- investment, net	161,850	338,270
Repurchase agreements	3,489,511	2,685,203
Loan participations sold, net	167,744	516,484
Notes payable, net	48,000	303,515
Secured term loan, net	739,762	746,095
Debt related to real estate owned, net	289,806
Level 3 [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans receivable held-for-investment, net	6,434,157	6,155,526
Interests in loans receivable held-for- investment, net	161,883	338,695
Repurchase agreements	3,484,834	2,668,464
Loan participations sold, net	168,738	524,010
Notes payable, net	48,000	308,069
Secured term loan, net	762,717	769,949
Debt related to real estate owned, net	281,723
Par Value [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans receivable held-for-investment, net	6,441,238	6,152,331
Interests in loans receivable held-for- investment, net	161,566	338,957
Repurchase agreements	3,489,511	2,685,203
Loan participations sold, net	168,322	519,420
Notes payable, net	48,000	305,294
Secured term loan, net	762,717	768,554
Debt related to real estate owned, net	290,000
Fair Value [Member]
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Loans receivable held-for-investment, net	6,434,157	6,155,526
Interests in loans receivable held-for- investment, net	161,883	338,695
Repurchase agreements	3,484,834	2,668,464
Loan participations sold, net	168,738	524,010
Notes payable, net	48,000	308,069
Secured term loan, net	762,717	$ 769,949
Debt related to real estate owned, net	$ 281,723

Debt related to real estate owned net.

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Debt related to real estate owned, net.

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- Definition

Interest In Loans Held To Maturity Fair Value Disclosure.

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Interests in loans receivable held-for-investment.

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No definition available.

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Loan Participations Sold Fair Value Disclosure.

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Loan participations sold, net.

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Loans held to maturity fair value disclosure.

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No definition available.

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Loans receivable held-for-investment.

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No definition available.

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Notes payable, net.

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No definition available.

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The fair value amount of debt related to real estate owned.

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No definition available.

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Repurchase agreements.

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No definition available.

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- Definition

Secured term loan.

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No definition available.

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- Definition

Fair value portion of borrowing as secured term loans.

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No definition available.

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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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No definition available.

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Amount of loan with fixed rate of interest.

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Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer.

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Fair value portion of notes payable.

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The aggregate amount of the participation liability at the end of the accounting period.

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- Definition

Fair value portion of receivables, including, but not limited to, trade account receivables, note receivables, and loan receivables.

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Carrying value, as of the balance sheet date, of securities sold under agreements to repurchase where the transferor maintains effective control over the assets, accounting for them as secured debt.

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Carrying amount of collateralized debt obligations with maturities initially due after one year or beyond the operating cycle, if longer, excluding the current portion. Obligations include, but not limited to, mortgage loans, chattel loans, and other borrowings secured by assets.

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Fair value of securities pledged as collateral against securities sold under agreement to repurchase.

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