XML 79 R45.htm IDEA: XBRL DOCUMENT v3.20.4

Marketable Securities - Summary of Cash Equivalents and Marketable Securities Recorded at Fair Value (Detail) $ in Thousands	Dec. 31, 2020 USD ($)
Marketable Securities [Line Items]
Cash equivalents, amortized cost	$ 773,560
Cash equivalents, gross unrealized gains	1
Cash equivalents, gross unrealized losses	(24)
Cash equivalents, fair value	773,537
Marketable securities, amortized cost	521,820
Marketable securities, gross unrealized gains	51
Marketable securities, gross unrealized losses	(158)
Marketable securities, fair value	521,713
Cash equivalents and marketable securities, amortized cost	1,295,380
Cash equivalents and marketable securities, gross unrealized gains	52
Cash equivalents and marketable securities, gross unrealized losses	(182)
Cash equivalents and marketable securities, fair value	1,295,250
Money Market Funds [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	742,958
Cash equivalents, fair value	742,958
Certificates of Deposit [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	12,527
Cash equivalents, fair value	12,527
Marketable securities, amortized cost	25,162
Marketable securities, fair value	25,162
Commercial Paper [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	15,549
Cash equivalents, fair value	15,549
Marketable securities, amortized cost	90,375
Marketable securities, fair value	90,375
US Treasury Securities [Member]
Marketable Securities [Line Items]
Marketable securities, amortized cost	47,976
Marketable securities, gross unrealized gains	3
Marketable securities, fair value	47,979
Corporate Debt Securities [Member]
Marketable Securities [Line Items]
Cash equivalents, amortized cost	2,526
Cash equivalents, gross unrealized gains	1
Cash equivalents, gross unrealized losses	(24)
Cash equivalents, fair value	2,503
Marketable securities, amortized cost	324,569
Marketable securities, gross unrealized gains	43
Marketable securities, gross unrealized losses	(156)
Marketable securities, fair value	324,456
Government-sponsored Enterprise Securities [Member]
Marketable Securities [Line Items]
Marketable securities, amortized cost	33,738
Marketable securities, gross unrealized gains	5
Marketable securities, gross unrealized losses	(2)
Marketable securities, fair value	$ 33,741

X

- Definition

Cash equivalents and available for sale debt securities amortized cost basis.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsAndAvailableForSaleDebtSecuritiesAmortizedCostBasis
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Cash equivalents and available for sale debt securities fair value.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsAndAvailableForSaleDebtSecuritiesFairValue
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Cash equivalents and available for sale debt securities gross unrealized gains before tax.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsAndAvailableForSaleDebtSecuritiesGrossUnrealizedGainsBeforeTax
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Cash equivalents and available for sale debt securities gross unrealized losses before tax.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsAndAvailableForSaleDebtSecuritiesGrossUnrealizedLossesBeforeTax
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Cash equivalents fair value.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsFairValue
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Cash equivalents gross unrealized gain before tax.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsGrossUnrealizedGainsBeforeTax
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Cash equivalents gross unrealized losses before tax.

+ References

No definition available.

+ Details

Name:	crsp_CashEquivalentsGrossUnrealizedLossesBeforeTax
Namespace Prefix:	crsp_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

Name:	us-gaap_AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

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

X

- Definition

Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

+ Details

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

X

- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121558606&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121553693&loc=d3e26610-111562

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

+ Details

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

X

- Definition

Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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

X

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

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_MoneyMarketFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CertificatesOfDepositMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_InvestmentTypeAxis=us-gaap_CommercialPaperMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USTreasurySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_USGovernmentSponsoredEnterprisesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: