0001429260 us-gaap:CommonStockMember 2026-05-14 2026-05-14 0001429260 fbio:SeriesCumulativeRedeemablePerpetualPreferredStockMember 2026-05-14 2026-05-14 0001429260 2026-05-14 2026-05-14 0001429260 false 8-K 2026-05-14 Fortress Biotech, Inc. DE 001-35366 20-5157386 1111 Kane Concourse Suite 301 Bay Harbor Islands FL 33154 781 652-4500 false false false false Common Stock FBIO NASDAQ 9.375% Series A Cumulative Redeemable Perpetual Preferred Stock FBIOP NASDAQ false