XML 15 R7.htm IDEA: XBRL DOCUMENT
v3.24.3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) (Parenthetical) $ in Millions | 9 Months Ended
--- | ---
Sep. 30, 2023 USD ($)
Statement Of Cash Flows [Abstract] |
Offering cost | $ 0.2

X
- Definition Offering costs. + References No definition available. + Details
Name: | pstv_OfferingCosts
Namespace Prefix: | pstv_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- References No definition available. + Details
Name: | us-gaap_StatementOfCashFlowsAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration