Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Debt Securities, Available-for-sale [Line Items]
Estimated Fair Value	$ 47,099	$ 20,821
Interest receivable	709	125
U.S. government agency bonds
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	46,372	20,686
Gross Unrealized Gains	727	135
Estimated Fair Value	$ 47,099	$ 20,821

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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+ Details

DELCATH SYSTEMS, INC. 10-Q