The amount of milestone payment the Company is eligible to receive as part of a license agreement.

No definition available.

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Namespace Prefix:	dcph_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of upfront payment to be received as part of a license agreement.

+ References

No definition available.

+ Details

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

- Definition

The amount of revenue recognized during the period for the upfront payment of a license agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4531-111522

+ Details

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

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-Subparagraph (a)
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-Publisher FASB
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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03(1))
-URI http://asc.fasb.org/extlink&oid=116634182&loc=SL114868664-224227

+ Details

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

- Details

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Namespace Prefix:
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Period Type:

- Details

Name:	srt_ProductOrServiceAxis=us-gaap_LicenseMember
Namespace Prefix:
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Balance Type:
Period Type:

- Details

Name:	dcph_MilestoneAxis=dcph_DevelopmentAndCommercialMilestoneMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_RangeAxis=srt_MaximumMember
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Balance Type:
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- Details

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Namespace Prefix:
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- Details

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- Details

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- Details

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License Agreement - Additional Information (Details) - USD ($)	1 Months Ended	3 Months Ended
	Jun. 30, 2019	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2019
Zai License Agreement
Upfront cash payment receivable					$ 20,000,000.0
Upfront payment recognized revenue			$ 20,000,000.0
Zai License Agreement \| License
Revenues		$ 0	25,000,000.0	$ 0
Zai License Agreement \| Development And Commercial Milestone \| Maximum
License agreement milestone	$ 185,000,000.0
Zai License Agreement \| Development Milestone \| INTRIGUE Study Related Milestone
License agreement milestone			$ 5,000,000.0
Zai License Agreement \| Development Milestone \| Maximum
License agreement milestone	50,000,000.0
Zai License Agreement \| Commercial Milestone \| Maximum
License agreement milestone	$ 135,000,000.0
Zai Supply Agreement \| License
Revenues		100,000
Accounts receivable		$ 100,000