Business Combinations - Schedule of Revenue and Earnings (Details) - NewPoint Holdings JV LLC - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2026
Business Combination [Line Items]
Revenue	$ 41,474	$ 99,080
Net income (loss) attributable to Franklin BSP Realty Trust, Inc.	$ 1,116	$ (2,858)

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