Payment of consulting, licensing and other fees to related party.

No definition available.

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- Definition

Percentage of remaining ordinary share capital of subsidiary not owned by parent.

+ References

No definition available.

+ Details

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Namespace Prefix:	crspr_
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- Definition

Represents the additional amount of fees expense incurred with related parties.

+ References

No definition available.

+ Details

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

- Definition

Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

+ Details

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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

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

- Definition

The amount of compensation earned (contract income) under a research and development arrangement accounted for as a contract to perform research and development for others.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23199-108380

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6420387&loc=d3e23221-108380

+ Details

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

- Details

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- Details

Name:	us-gaap_StatementClassOfStockAxis=crspr_SeriesA3RedeemableConvertiblePreferredStockMember
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- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=crspr_DrEmmanuelleCharpentierMember
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- Details

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- Details

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Related Party Transactions - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Investors [Member] \| Series A-3 Redeemable Convertible Preferred Shares [Member]
Related Party Transaction [Line Items]
Legal and consulting costs			$ 200,000
Dr. Emmanuelle Charpentier [Member] \| TRACR Hematology Limited [Member]
Related Party Transaction [Line Items]
Noncontrolling interest in TRACR			17.90%
Payment of consulting, licensing and other fees	$ 17,000	$ 8,000	$ 1,000,000	$ 25,000
Related party transaction additional fees			300,000		$ 1,000,000
Bayer Healthcare LLC [Member]
Related Party Transaction [Line Items]
Revenue related to research and development services	$ 400,000	$ 0	$ 400,000	$ 0