Collateralized Loan Obligations - Schedule of Collateral Assets and Respective Borrowings (Details) - Primary beneficiary - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025
Collateralized loan obligations, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Outstanding principal, financing provided	$ 0
Carrying value, financing provided	$ 0	$ 1,198,332
Weighted average yield, financing provided	0.00%
Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 0
Outstanding principal, collateral assets	0
Carrying value, collateral assets	0
KREF 2021-FL2 \| Collateralized loan obligations, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Outstanding principal, financing provided	0
Carrying value, financing provided	$ 0	654,964
Weighted average yield, financing provided	0.00%
KREF 2021-FL2 \| Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 0
Outstanding principal, collateral assets	0
Carrying value, collateral assets	0
KREF 2022-FL3 \| Collateralized loan obligations, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Outstanding principal, financing provided	0
Carrying value, financing provided	$ 0	$ 543,368
Weighted average yield, financing provided	0.00%
KREF 2022-FL3 \| Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 0
Outstanding principal, collateral assets	0
Carrying value, collateral assets	$ 0

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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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Face (par) amount of debt instrument at time of issuance.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Carrying amount of financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

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