Stockholders' Equity - Common Stock Issuances - Additional Information (Details)	3 Months Ended
Mar. 31, 2021 shares
Stockholders Equity Note [Abstract]
Common stock associated with the exercise of warrants	237,520

Stock Issued During Period Shares associated with warrants.

No definition available.

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Namespace Prefix:	dcth_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration