Aggregate milestone payments.

No definition available.

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

- Definition

Aggregate payment on collaboration agreement to be received.

+ References

No definition available.

+ Details

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

- Definition

Commercial milestone payments.

+ References

No definition available.

+ Details

Name:	dtil_CommercialMilestonePayments
Namespace Prefix:	dtil_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Development and commercial milestone payments.

+ References

No definition available.

+ Details

Name:	dtil_DevelopmentAndCommercialMilestonePayments
Namespace Prefix:	dtil_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Development milestone payments.

+ References

No definition available.

+ Details

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

- Definition

Receivable from research funding.

+ References

No definition available.

+ Details

Name:	dtil_ReceivableFromResearchFunding
Namespace Prefix:	dtil_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Research funding payment term.

+ References

No definition available.

+ Details

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Namespace Prefix:	dtil_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Upfront payment.

+ References

No definition available.

+ Details

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

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130531-203044

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=118944033&loc=SL49130532-203044

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

+ Details

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

- Definition

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130549-203045

+ Details

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

- Definition

The cash outflows from the purchase of net carrying value allocated to in-process research and development costs and materials acquired in a business combination.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

+ Details

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

- Definition

Cash received from collaborators during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3536-108585

+ Details

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

- Details

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Balance Type:
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- Details

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- Details

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- Details

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- Details

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- Details

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Collaboration and License Agreements - Additional Information (Details) - USD ($)			9 Months Ended
	Sep. 10, 2018	Feb. 24, 2016	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Collaboration and License Agreements [Line items]
Revenue recorded included in deferred revenue			$ 6,400,000
Deferred revenue			10,767,000		$ 8,436,000
Development and Commercial License Agreement \| Servier
Collaboration and License Agreements [Line items]
Upfront payment		$ 105,000,000
Revenue recorded included in deferred revenue			4,400,000	$ 4,300,000
Deferred revenue			83,800,000		88,600,000
Development or sales-based milestone payments			0	0
Development and Commercial License Agreement \| Servier \| Current Liabilities
Collaboration and License Agreements [Line items]
Deferred revenue			5,900,000		5,800,000
Development and Commercial License Agreement \| Servier \| Maximum
Collaboration and License Agreements [Line items]
Total payments to be received		1,600,000,000
Aggregate milestone payments		1,500,000,000
Development milestone payments		401,300,000
Commercial milestone payments		$ 1,100,000,000
Collaboration and License Agreement \| Gilead
Collaboration and License Agreements [Line items]
Revenue recorded included in deferred revenue			10,000,000	$ 700,000
Deferred revenue			4,900,000		2,300,000
Development or sales-based milestone payments			$ 0
Research funding payment term	3 years		3 years
Semi-annual research funding payments	$ 40,000,000
Collaboration and License Agreement \| Gilead \| Current Liabilities
Collaboration and License Agreements [Line items]
Deferred revenue			$ 4,900,000		$ 2,300,000
Collaboration and License Agreement \| Gilead \| Maximum
Collaboration and License Agreements [Line items]
Development milestone payments	105,000,000
Commercial milestone payments	340,000,000
Receivable from research funding	40,000,000
Development and commercial milestone payments	$ 445,000,000