v3.26.1

Fair Value of Financial Instruments - Schedule of Changes in the Company's Financial Instruments Classified as Level III (Details) - Fair Value, Measurements, Recurring - Level III - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2026	Dec. 31, 2025
Commercial mortgage loans, held for sale, measured at fair value - Non-Agency
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	$ 29,500	$ 87,270
Transfers into Level III	0	0
Originations	251,250	411,650
Sales/paydowns	(109,344)	(487,529)
Realized and unrealized gain/(loss) included in earnings	4,344	18,109
Transfers out of Level III	0	0
Ending balance	175,750	29,500
Commercial mortgage loans, held for sale, measured at fair value - Agency
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	331,218	0
Transfers into Level III	0	422,011
Originations	584,746	3,225,586
Sales/paydowns	(668,683)	(3,316,379)
Realized and unrealized gain/(loss) included in earnings	0	0
Transfers out of Level III	0	0
Ending balance	247,281	331,218
Loan commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	10,518	0
Transfers into Level III	0	4,268
Originations	10,100	32,961
Sales/paydowns	(8,713)	(26,711)
Realized and unrealized gain/(loss) included in earnings	0	0
Transfers out of Level III	0	0
Ending balance	11,905	10,518
Forward sale commitments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance	(5,413)	0
Transfers into Level III	0	0
Originations	6,906	(5,413)
Sales/paydowns		0
Realized and unrealized gain/(loss) included in earnings	0	0
Transfers out of Level III	0	0
Ending balance	$ 1,493	$ (5,413)

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings, Sale of Commercial Mortgage Loan Held For Sale

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Franklin BSP Realty Trust, Inc. 10-Q