Subsequent Event - Additional Information (Detail) - Subsequent Event - Metenova AB $ in Millions	Oct. 02, 2023 USD ($)
Subsequent Event [Line Items]
Business combination date of acquistion	Oct. 02, 2023
Cash Acquired from Acquisition	$ 173

Date when the acquirer obtains control of the acquiree, in YYYY-MM-DD format.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Paragraph 7
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-Topic 805
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 25
-Paragraph 6
-SubTopic 10
-Topic 805
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479405/805-10-25-6

+ Details

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

- Definition

The cash inflow associated with the acquisition of business during the period (for example, cash that was held by the acquired business).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-12

+ Details

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

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

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-Topic 855
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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_BusinessAcquisitionAxis=rgen_MetenovaAbMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: