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Secured Debt, Net - Schedule of Secured Credit Facilities (Detail) $ in Thousands	9 Months Ended
	Sep. 30, 2025 USD ($) loan lender	Dec. 31, 2024 USD ($)
Schedule Of Secured Credit Facilities [Line Items]
Total face value	$ 13,037,822
Secured debt, net | Secured debt, net
Schedule Of Secured Credit Facilities [Line Items]
Collateral	$ 2,900,000
Secured debt, net | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Lenders | lender	13
Total face value	$ 9,548,332	$ 9,705,529
Loan Count | loan	112
Collateral	$ 14,083,177	$ 14,807,821
Secured debt, net | Weighted Average | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	31.00%
Secured debt, net | Minimum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%
Secured debt, net | Maximum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	100.00%
Secured debt, net | USD | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Lenders | lender	12
Total face value	$ 3,954,253
Loan Count | loan	81
Collateral	$ 6,522,111
Secured debt, net | USD | Weighted Average | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	32.00%
Secured debt, net | USD | Minimum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%
Secured debt, net | USD | Maximum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	100.00%
Secured debt, net | GBP | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Lenders | lender	6
Total face value	$ 2,265,827
Loan Count | loan	14
Collateral	$ 3,098,509
Secured debt, net | GBP | Weighted Average | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%
Secured debt, net | GBP | Minimum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%
Secured debt, net | EUR | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Lenders | lender	7
Total face value	$ 1,835,792
Loan Count | loan	10
Collateral	$ 2,588,781
Secured debt, net | EUR | Weighted Average | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	42.00%
Secured debt, net | EUR | Minimum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%
Secured debt, net | EUR | Maximum | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	100.00%
Secured debt, net | Others | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Lenders | lender	4
Total face value	$ 1,492,460
Loan Count | loan	7
Collateral	$ 1,873,776
Recourse Limitation	25.00%
Secured debt, net | Others | Weighted Average | Secured debt, net | Secured credit facilities
Schedule Of Secured Credit Facilities [Line Items]
Recourse Limitation	25.00%

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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-Publisher FASB
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-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
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