v3.25.3

Stockholders' Equity - Employee Stock Purchase Plan (Details) - May 2022 Employee Stock Purchase Plan - shares		1 Months Ended
	May 15, 2025	Aug. 31, 2021	Sep. 30, 2025
Employee Stock Ownership Plan (ESOP) Disclosures [Line Items]
Number of shares authorized (in shares)		560,295	171,364
Number of additional shares authorized (in shares)	300,000
Purchase price of common stock (as a percent)		85.00%
Offering period		6 months

Share-based Compensation Arrangement By Share-based Payment Award, Stock Plan Offering Period

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- Definition

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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-Topic 718
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-Name Accounting Standards Codification
-Section 50
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- Definition

Number of additional shares authorized for issuance under share-based payment arrangement.

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-Topic 718
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-Name Accounting Standards Codification
-Section 50
-Paragraph 4
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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Topic 718
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-Section 50
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DELCATH SYSTEMS, INC. 10-Q