XML 35 R25.htm IDEA: XBRL DOCUMENT
v3.20.2

Commitments and Contingencies (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2020
Commitments [Abstract] |
Summary of Lease Liabilities and Right-of-Use Assets | The table below summarizes the Company’s lease liabilities and corresponding right-of-use assets (in thousands, except year and rates):
| As of September 30, 2020 |
Assets |  |  |
Operating | $ | 671 |
Financing | 39 |
Total leased assets | $ | 710 |
Liabilities |  |  |
Current: |  |  |
Operating | $ | 140 |
Financing | 39 |
Noncurrent: |  |  |
Operating | 545 |
Financing |  | — |
Total lease liabilities | $ | 724 |
Weighted-average remaining lease term (years) - operating leases | 6.53 |
Weighted-average remaining lease term (years) - finance leases | 0.37 |
Weighted-average discount rate - operating leases |  | 7.9 | %
Weighted-average discount rate - finance leases |  | 5.0 | %
Summary of Lease Costs | The table below summarizes the Company’s lease costs from its consolidated condensed statement of operations and comprehensive loss, and cash payments from its consolidated condensed statement of cash flows during the three and nine months ended September 30, 2020 (in thousands):
| Three Months Ended |  |  | Nine Months Ended |
| September 30, 2020 |  | September 30, 2019 |  |  | September 30, 2020 |  | September 30, 2019 |
Lease expense: |  |  |  |  |  |  |  |  |  |  |  |  |
Operating lease expense | $ | 52 |  | $ | 56 |  |  | $ | 160 |  | $ | 169 |
Finance lease expense: |  |  |  |  |  |  |  |  |  |  |  |  |
Depreciation of right-of-use assets |  | 32 |  | 32 |  |  | 95 |  | 85 |
Interest expense on lease liabilities | 1 |  | 2 |  |  | 4 |  | 7 |
Total lease expense | $ | 85 |  | $ | 90 |  |  | $ | 259 |  | $ | 261 |
Cash payment information: |  |  |  |  |  |  |  |  |  |  |  |  |
Operating cash used for operating leases | $ | 56 |  | $ | 38 |  |  | $ | 155 |  | $ | 147 |
Financing cash used for financing leases | 42 |  | 1 |  |  | 93 |  | 75 |
Total cash paid for amounts included in the measurement of lease liabilities | $ | 98 |  | $ | 39 |  |  | $ | 248 |  | $ | 222 |
Summary of Future Minimum Annual Lease Payments under Operating and Financing Leases | Total rent expense for the three and nine months ended September 30, 2020 was $48,000 and $177,000, respectively, which includes leases in the table above, month-to-month operating leases, and common area maintenance charges. The Company’s future minimum annual lease payments under operating and financing leases at September 30, 2020 are as follows in (thousands):
|  | Financing Leases |  |  | Operating Leases |
Remaining 2020 |  | $ | 32 |  |  | $ | 49 |
2021 |  | 7 |  |  | 183 |
2022 |  | — |  |  | 123 |
2023 |  | — |  |  | 100 |
Thereafter |  | — |  |  | 447 |
Total minimum lease payments |  | $ | 39 |  |  | $ | 902 |
Less: amount representing interest |  |  | — |  |  |  | (217 | )
Present value of obligations under leases |  |  | 39 |  |  |  | 685 |
Less: current portion |  |  | 39 |  |  |  | (140 | )
Noncurrent lease obligations |  | $ | — |  |  | $ | 545 |

X
- Definition Commitments. + References No definition available. + Details
Name: | pstv_CommitmentsAbstract
Namespace Prefix: | pstv_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of operating and financing lease liability maturity. + References No definition available. + Details
Name: | pstv_ScheduleOfOperatingAndFinancingLeaseLiabilityMaturityTableTextBlock
Namespace Prefix: | pstv_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Schedule of right of use assets and lease liabilities. + References No definition available. + Details
Name: | pstv_ScheduleOfRightOfUseAssetsAndLeaseLiabilitiesTableTextBlock
Namespace Prefix: | pstv_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Definition Tabular disclosure of lessee's lease cost. Includes, but is not limited to, interest expense for finance lease, amortization of right-of-use asset for finance lease, operating lease cost, short-term lease cost, variable lease cost and sublease income. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
Name: | us-gaap_LeaseCostTableTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration