Increase in lease rent expenses.

No definition available.

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Namespace Prefix:	dcth_
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Balance Type:	debit
Period Type:	duration

- Definition

Sub Lease Rent Expense

+ References

No definition available.

+ Details

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Namespace Prefix:	dcth_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Area of land held.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:areaItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of lessor's operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919359-209981

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Description of terms and conditions of option to extend lessor's operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=124258985&loc=SL77919359-209981

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=123414884&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918686-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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Namespace Prefix:
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- Details

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Leases - Additional Information (Details)			12 Months Ended
Leases - Additional Information (Details)	Jul. 01, 2020 USD ($) ft²	Jun. 25, 2020 USD ($)	Dec. 31, 2021 USD ($)	Sep. 22, 2020 ft²
Rent per month			$ 564,000
Lease term			12 months
Two Thousand Fifteen Sublease Agreement
Lease, description	the 2014 Sublease and 2015 Sublease were extended from May 31, 2020 to August 2, 2021, (ii) effective July 1, 2020, the leased premises under the 2015 Sublease would be expanded to include an additional 4,999 square feet of space, and (iii) effective July 1, 2020, the rent under the 2015 Sublease would increase from approximately $14.6 per month to $20.6 per month.
Additional area of space \| ft²	4,999
Extension of sublease	May 31, 2020 to August 2, 2021
Two Thousand Fifteen Sublease Agreement \| Minimum [Member]
Increase in sublease rent	$ 20,600
Two Thousand Fifteen Sublease Agreement \| Maximum [Member]
Increase in sublease rent	$ 14,600
2021 Sub-Lease [Member]
Rent per month		$ 3,700
Lease term		5 years
Additional area of space \| ft²				6,877
Sub lease rent			$ 406,000