Restricted beneficial ownership level result of exercise of warrant to receive pre-funded warrant.

No definition available.

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Namespace Prefix:	pstv_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of expense (income) related to adjustment to fair value of warrant liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 25
-Paragraph 13
-SubTopic 10
-Topic 480
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481766/480-10-25-13

+ Details

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Balance Type:	debit
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- 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-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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Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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Subsequent Events - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended	6 Months Ended
	Aug. 09, 2024	Jun. 30, 2024	Jun. 30, 2024
Subsequent Event [Line Items]
Gain on change in fair value of warrant liabilities		$ (4,694)	$ (4,694)
Series A Warrant [Member] \| Amendment and Restatements May 2024 Private Placement [Member] \| Common Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Restricted Beneficial Ownership Level Result of Exercise of Warrant To Receive Pre-funded Warrant	4.99%
Series B Warrant [Member] \| Amendment and Restatements May 2024 Private Placement [Member] \| Common Stock [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Restricted Beneficial Ownership Level Result of Exercise of Warrant To Receive Pre-funded Warrant	9.99%