Collateralized Loan Obligations - Schedule of Collateral Assets and Respective Borrowings (Details) - Primary beneficiary - USD ($) $ in Thousands	Jun. 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	$ 660,361
Carrying value, financing provided	$ 660,342	$ 1,198,332
Weighted average yield, financing provided	5.70%
Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 660,361
Outstanding principal, collateral assets	1,015,614
Carrying value, collateral assets	907,742
KREF 2021-FL2 \| Collateralized loan obligations, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Outstanding principal, financing provided	327,124
Carrying value, financing provided	$ 327,124	654,964
Weighted average yield, financing provided	5.60%
KREF 2021-FL2 \| Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 327,124
Outstanding principal, collateral assets	531,874
Carrying value, collateral assets	425,058
KREF 2022-FL3 \| Collateralized loan obligations, net
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Outstanding principal, financing provided	333,237
Carrying value, financing provided	$ 333,218	$ 543,368
Weighted average yield, financing provided	5.80%
KREF 2022-FL3 \| Collateralized loan obligations
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Maximum Facility Size	$ 333,237
Outstanding principal, collateral assets	483,740
Carrying value, collateral assets	$ 482,684

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