Organization and Description of Business (Narrative) (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) company subsidiary
Organization and Description of Business
Number of partner companies that are publicly traded \| company	3
Number of partner companies that have consummated strategic partnerships with industry leaders \| subsidiary	4
Cash and cash equivalents, Parent Company \| $	$ 209.9

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits for the parent company. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

No definition available.

Name:	fbio_CashAndCashEquivalentsParentCompany
Namespace Prefix:	fbio_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant