XML 72 R60.htm IDEA: XBRL DOCUMENT
v3.25.3

Commitments and Contingencies (Details) | 1 Months Ended | 3 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2024 USD ($) | Sep. 30, 2023 USD ($) | Aug. 31, 2021 USD ($) | Jul. 31, 2021 USD ($) | Oct. 31, 2020 | Mar. 31, 2020 USD ($) | Feb. 29, 2020 USD ($) | Oct. 31, 2018 USD ($) | Mar. 31, 2025 USD ($) | Sep. 30, 2025 USD ($) letterOfCredit | Dec. 31, 2024 USD ($) | Sep. 30, 2024 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of outstanding letters of credit | letterOfCredit |  |  |  |  |  |  |  |  |  | 4 |  |
Outstanding letters of credit amount |  |  |  |  |  |  |  |  |  | $ 1,800,000 |  |
Restricted cash |  |  |  |  |  |  |  |  |  | 3,680,000 | $ 3,239,000 | $ 3,217,000
Jerome Treadwell v. The Company |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Recovery per negligent violation |  |  |  |  |  |  |  | $ 1,000 |  |  |  |
Recovery per intentional or reckless violation |  |  |  |  |  |  |  | $ 5,000 |  |  |  |
Stay case term (in days) |  |  |  |  | 60 days |  |  |  |  |  |  |
Estimated liability |  |  |  |  |  |  |  |  |  |  | 2,400,000 |
Litigation settlement payment |  |  |  |  |  |  |  |  | $ 2,400,000 |  |  |
Payments for legal settlements |  |  |  |  |  |  |  |  | 700,000 |  |  |
Jerome Treadwell v. The Company | Insurance Carrier |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Payments for legal settlements |  |  |  |  |  |  |  |  | $ 1,700,000 |  |  |
Mast Powertrain v. The Company |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Estimated liability |  |  |  |  |  |  |  |  |  | $ 900,000 | $ 900,000 |
Litigation settlement payment |  |  |  | $ 1,500,000 |  |  |  |  |  |  |  |
Damages sought |  | $ 6,000,000 |  |  |  | $ 4,500,000 | $ 9,000,000.0 |  |  |  |  |
Gary Winemaster v. The Company |  |  |  |  |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Litigation settlement payment | $ 4,500,000 |  |  |  |  |  |  |  |  |  |  |
Damages sought |  |  | $ 7,200,000 |  |  |  |  |  |  |  |  |
Legal settlement |  |  | $ 8,800,000 |  |  |  |  |  |  |  |  |

X
- Definition Loss Contingency, Damages Sought, Value Per Intentional Violation + References No definition available. + Details
Name: | psix_LossContingencyDamagesSoughtValuePerIntentionalViolation
Namespace Prefix: | psix_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Loss Contingency, Damages Sought, Value Per Negligent Violation + References No definition available. + Details
Name: | psix_LossContingencyDamagesSoughtValuePerNegligentViolation
Namespace Prefix: | psix_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Loss Contingency, Stay Case, Term + References No definition available. + Details
Name: | psix_LossContingencyStayCaseTerm
Namespace Prefix: | psix_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number Of Outstanding Letters Of Credit + References No definition available. + Details
Name: | psix_NumberOfOutstandingLettersOfCredit
Namespace Prefix: | psix_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-15 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 944 -SubTopic 605 -Name Accounting Standards Codification -Section 55 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147477548/944-605-55-12 + Details
Name: | us-gaap_LettersOfCreditOutstandingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of litigation expense, including but not limited to legal, forensic, accounting, and investigative fees. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Name Accounting Standards Codification -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(6)) -SubTopic 10 -Topic 220 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483621/220-10-S99-2 + Details
Name: | us-gaap_LitigationSettlementExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 275 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482861/275-10-50-9 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-4 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-9 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 720 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483359/720-20-50-1 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 27 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482395/460-10-55-27 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-9 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-4 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 460 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482425/460-10-50-3 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of loss contingency liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 Reference 2: http://www.xbrl.org/2003/role/recommendedDisclosureRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 10 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-10 + Details
Name: | us-gaap_LossContingencyAccrualAtCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-4 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 450 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147483076/450-20-50-9 + Details
Name: | us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The amount of cash paid for the settlement of litigation or for other legal issues during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Section 45 -Paragraph 25 -Subparagraph (g) -SubTopic 10 -Topic 230 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482740/230-10-45-25 + Details
Name: | us-gaap_PaymentsForLegalSettlements
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of cash restricted as to withdrawal or usage, classified as current. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482913/230-10-50-8 + Details
Name: | us-gaap_RestrictedCashCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | srt_LitigationCaseAxis=psix_JeromeTreadwellv.TheCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | dei_LegalEntityAxis=psix_InsuranceCarrierMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=psix_MastPowertrainV.TheCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_LitigationCaseAxis=psix_GaryWinemasterVersusTheCompanyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |