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Fair Values - Schedule of Details of Book Value, Face Amount, and Fair Value of Financial Instruments (Detail) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Financial assets |  |
Cash and cash equivalents, book value | $ 377,921 | $ 323,483
Cash and cash equivalents, fair value | 377,921 | 323,483
Loans receivable, net, book value | 17,371,200 | 18,313,582
Loan receivable, net, face amount | 18,188,534 | 19,203,126
Loan receivable, net, fair value | 17,407,513 | 18,288,958
Financial liabilities |  |
Long-term debt, face amount | 13,037,822 |
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 | 9,540,224 | 9,696,334
Long-term debt, face amount | 9,548,332 | 9,705,529
Long-term debt, fair value | 9,450,250 | 9,590,400
Securitized debt obligations, net |  |
Financial liabilities |  |
Long-term debt | 2,470,067 | 1,936,956
Long-term debt, face amount | 2,479,417 | 1,936,967
Long-term debt, fair value | 2,455,101 | 1,838,089
Asset-specific debt, net |  |
Financial liabilities |  |
Long-term debt | 627,916 | 1,224,841
Long-term debt, face amount | 629,890 | 1,228,110
Long-term debt, fair value | 619,599 | 1,218,639
Secured term loans, net |  |
Financial liabilities |  |
Long-term debt | 1,774,913 | 1,732,073
Long-term debt, face amount | 1,808,127 | 1,764,437
Long-term debt, fair value | 1,812,573 | 1,765,668
Senior secured notes, net |  |
Financial liabilities |  |
Long-term debt | 785,215 | 771,035
Long-term debt, face amount | 785,316 | 785,316
Long-term debt, fair value | 801,487 | 780,931
Convertible notes, net |  |
Financial liabilities |  |
Long-term debt | 264,463 | 263,616
Long-term debt, face amount | 266,157 | 266,157
Long-term debt, fair value | $ 262,899 | $ 257,707

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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-11 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 825 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482907/825-10-50-10 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 5: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
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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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -SubTopic 10 -Topic 210 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Topic 942 -SubTopic 210 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 470 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481139/470-20-50-4 + Details
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- Definition Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 + Details
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