Derivative Instruments - Schedule of Derivative Instruments, Gain (Loss) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss)	$ (1,073)	$ 1,050	$ (140)
Realized gain/(loss)	873	(1,261)	998
Credit default swaps
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss)	(77)	75	41
Realized gain/(loss)	(50)	(112)	(36)
Interest rate swaps
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss)	0	0	(90)
Realized gain/(loss)	0	0	672
Options
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss)	22	83	0
Realized gain/(loss)	(256)	(90)	0
Treasury note futures
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss)	(1,018)	892	(91)
Realized gain/(loss)	$ 1,179	$ (1,059)	$ 362

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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+ Details

- Definition

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

+ References + Details

Franklin BSP Realty Trust, Inc. 10-K