Net Income (Loss) Per Share - Narrative (Details) - shares	Dec. 31, 2025	Dec. 31, 2024
Earnings Per Share [Abstract]
Pre-funded penny warrants outstanding	1,341,375	1,341,375

Number of shares pre-funded penny warrants outstanding.

No definition available.

Name:	dcth_NumberOfSharesPreFundedPennyWarrantsOutstanding
Namespace Prefix:	dcth_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant