Implicit interest rate.

No definition available.

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Namespace Prefix:	rptx_
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Balance Type:	na
Period Type:	duration

- Definition

Lessee operating lease expiration month and year.

+ References

No definition available.

+ Details

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Namespace Prefix:	rptx_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of operating leases.

+ References

No definition available.

+ Details

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

- Definition

Indicates (true false) whether lessee has option to extend operating lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

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Period Type:	duration

- Definition

Indicates (true false) whether lessee has option to terminate operating lease.

+ References

+ Details

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Period Type:	duration

- Definition

Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918673-209980

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Definition

Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Amount of the fee for available but unused credit capacity under the credit facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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

- Definition

Amount of asset related to consideration paid in advance for rent that provides economic benefits within a future period of one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 05
-Paragraph 5
-Subparagraph (c)
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-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6387103&loc=d3e6435-108320

+ Details

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

- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=rptx_OfficeAndLaboratorySpaceMember
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Period Type:

- Details

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Leases - Additional Information (Details) $ in Thousands	1 Months Ended			12 Months Ended
Leases - Additional Information (Details) $ in Thousands	Jun. 30, 2019	Nov. 30, 2017	Jun. 30, 2017	Dec. 31, 2020 USD ($) Lease	Nov. 30, 2019 USD ($)
Lessee Lease Description [Line Items]
Number of operating leases \| Lease				4
Lessee, operating lease, existence of option to terminate				false
Implicit interest rate				0.00%
Office and Laboratory Space \| Montreal, Quebec
Lessee Lease Description [Line Items]
Operating lease, term of contract		3 years	4 years		5 years
Operating lease, expiration month and year		2020-10	2021-07
Operating lease, existence of option to extend		true
Operating lease, option to extend, description		extended through October 2022
Prepaid rent					$ 1,000
Operating Lease, renewal term					5 years
Office and Laboratory Space \| Cambridge, Massachusetts
Lessee Lease Description [Line Items]
Operating lease, term of contract	2 years
Operating lease, expiration month and year	2021-05
Standby Letters of Credit \| Office and Laboratory Space \| Montreal, Quebec
Lessee Lease Description [Line Items]
Line of credit facility, unused amount				$ 212