Class of warrant or right warrants expiration period.

No definition available.

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- Definition

Number of common stock purchase warrant.

+ References

No definition available.

+ Details

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- Definition

Number of pre-funded warrants.

+ References

No definition available.

+ Details

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- Definition

Number of pre-funded warrants to purchase shares of common stock.

+ References

No definition available.

+ Details

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- Definition

Number of registered common stock offering.

+ References

No definition available.

+ Details

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- Definition

Number of shares to purchase upon common stock purchase warrant.

+ References

No definition available.

+ Details

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- Definition

Number of warrants to purchase aggregate shares of common stock.

+ References

No definition available.

+ Details

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- Definition

Offering share issued.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Purchase of common stock warrants, pre-funded warrants payable at closing, per share.

+ References

No definition available.

+ Details

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Period Type:	instant

- Definition

Purchase of common stock warrants, pre-funded warrants payable upon exercise, per share.

+ References

No definition available.

+ Details

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Namespace Prefix:	dcth_
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Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(4))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(i)(2))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

+ References

+ Details

Name:	us-gaap_CommonStockSharesAuthorized
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Data Type:	xbrli:sharesItemType
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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

+ Details

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Period Type:	instant

- Definition

Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644

+ Details

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Period Type:	instant

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Per share or per unit amount of equity securities issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB TOPIC 4.C)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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Subsequent Events - Additional Information (Details) $ / shares in Units, $ in Millions	Feb. 26, 2018 shares	Feb. 09, 2018 USD ($) $ / shares shares	Nov. 06, 2017	Jul. 21, 2016	Jul. 19, 2016 shares	Jan. 25, 2018 shares	Dec. 31, 2017 $ / shares shares	Dec. 31, 2016 $ / shares shares	Jul. 18, 2016 shares	Dec. 31, 2015 $ / shares	Dec. 31, 2014 $ / shares
Subsequent Event [Line Items]
Common stock, shares issued (in shares)							114,055,137	11,805
Common stock, shares outstanding (in shares)							114,054,851	11,750
Common stock, shares authorized (in shares)					500,000,000		500,000,000	500,000,000	170,000,000
Reverse stock split ratio			0.0029	0.0625
Minimum [Member]
Subsequent Event [Line Items]
Warrants exercisable per share price (in dollars per share) \| $ / shares							$ 2.45	$ 563.50		$ 4,144	$ 9,800
Reverse stock split ratio					0.1
Maximum [Member]
Subsequent Event [Line Items]
Warrants exercisable per share price (in dollars per share) \| $ / shares							$ 39,424	$ 39,424		$ 39,424	$ 39,424
Reverse stock split ratio					0.05
Subsequent Event [Member] \| Minimum [Member] \| Board of Directors [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)	500,000,000
Reverse stock split ratio	0.01
Subsequent Event [Member] \| Maximum [Member] \| Board of Directors [Member]
Subsequent Event [Line Items]
Common stock, shares authorized (in shares)	1,000,000,000
Reverse stock split ratio	0.002
Subsequent Event [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Number of registered common stock offering		212,000,000
Number of pre-funded warrants		38,000,000
Number of pre-funded warrants to purchase shares of common stock		38,000,000
Gross proceeds from sale of warrants \| $		$ 5.0
Offering price \| $ / shares		$ 0.02
Number of common stock purchase warrant		1
Number of shares to purchase upon common stock purchase warrant		2
Purchase of common stock warrants, pre-funded warrants shall be paid at offering, per unit \| $ / shares		$ 0.019
Purchase of common stock warrants, pre-funded warrants shall be paid upon exercise, per unit \| $ / shares		$ 0.001
Warrants expiration period		5 years
Warrants exercisable per share price (in dollars per share) \| $ / shares		$ 0.02
Common stock, shares issued (in shares)		434,981,824
Common stock, shares outstanding (in shares)		434,981,824
Subsequent Event [Member] \| Series D Warrants [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Number of warrants to purchase aggregate shares of common stock		500,000,000
Subsequent Event [Member] \| Common Stock Issued [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Offering share issued		1
Subsequent Event [Member] \| Warrants [Member] \| Registered Offering [Member]
Subsequent Event [Line Items]
Offering share issued		1
Exchange Agreement [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Shares issuable upon warrants exercised						108,900,000