Contingent payments upon achievement of specified milestones.

No definition available.

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Namespace Prefix:	rapt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Development milestone payment.

+ References

No definition available.

+ Details

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Namespace Prefix:	rapt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Unconstrained development milestone payment.

+ References

No definition available.

+ Details

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Namespace Prefix:	rapt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Upfront fees.

+ References

No definition available.

+ Details

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Namespace Prefix:	rapt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Upfront milestone payment.

+ References

No definition available.

+ Details

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Namespace Prefix:	rapt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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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- Definition

Amount of deferred income and obligation to transfer product and service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(5))
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+ Details

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Period Type:	instant

- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123359005&loc=d3e8906-108599

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-Publisher FASB
-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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+ Details

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Balance Type:	credit
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

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Collaboration Agreements - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Apr. 30, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenue recognized	$ 3,813,000	$ 5,042,000
Collaboration and License Agreement \| Hanmi Pharmaceutical Co., LTD
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront and near-term milestone payment				$ 10,000,000.0
Upfront fee				4,000,000.0
Development milestone payment			$ 6,000,000.0
Unconstrained development milestone payment		400,000		6,000,000.0
Revenue recognized	3,800,000	$ 5,000,000.0
Deferred revenue	$ 1,500,000
Collaboration and License Agreement \| Hanmi Pharmaceutical Co., LTD \| Maximum
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Contingent payments upon achievement of specified milestones				$ 108,000,000.0