Fair Values - Schedule of Details of Book Value, Face Amount, and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Financial assets
Cash and cash equivalents, book value	$ 452,526	$ 323,483
Cash and cash equivalents, fair value	452,526	323,483
Loans receivable, net, book value	17,784,694	18,313,582
Loan receivable, net, face amount	18,154,768	19,203,126	$ 23,923,719
Loan receivable, net, fair value	17,856,303	18,288,958
Financial liabilities
Long-term debt, face amount	14,024,848
Loan participations sold, net, book value	0	100,064
Loan participations sold, net, face amount	0	100,064
Loan participations sold, net, fair value	0	99,822
Secured debt, net
Financial liabilities
Long-term debt	10,117,292	9,696,334
Long-term debt, face amount	10,125,839	9,705,529
Long-term debt, fair value	10,029,890	9,590,400
Other secured debt, net
Financial liabilities
Long-term debt	39,475	0
Long-term debt, face amount	39,475	0
Long-term debt, fair value	39,475	0
Securitized debt obligations, net
Financial liabilities
Long-term debt	2,139,719	1,936,956
Long-term debt, face amount	2,149,496	1,936,967
Long-term debt, fair value	2,132,667	1,838,089
Asset-specific debt, net
Financial liabilities
Long-term debt	997,746	1,224,841
Long-term debt, face amount	999,810	1,228,110
Long-term debt, fair value	996,308	1,218,639
Secured term loans, net
Financial liabilities
Long-term debt	1,808,000	1,732,073
Long-term debt, face amount	1,847,726	1,764,437
Long-term debt, fair value	1,850,327	1,765,668
Senior secured notes, net
Financial liabilities
Long-term debt	784,876	771,035
Long-term debt, face amount	785,316	785,316
Long-term debt, fair value	810,608	780,931
Convertible notes, net
Financial liabilities
Long-term debt	264,745	263,616
Long-term debt, face amount	266,157	266,157
Long-term debt, fair value	$ 264,286	$ 257,707

Cash And Cash Equivalents

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- Definition

Loan Participation Liabilities, Principal Amount

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Loan Participations Sold, Liabilities, Fair Value

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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