XML 301 R77.htm IDEA: XBRL DOCUMENT
v3.25.2

Warrants (Details) - $ / shares | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024 | Sep. 11, 2024 | Apr. 08, 2024
Warrants |  |  |  |
Class of warrant or right outstanding | 23,200,000 | 23,200,000 |  |
Threshold maximum period for registration statement to become effective after business combination | 60 days | 60 days |  |
Threshold trading days for calculating Market Value | 20 days | 20 days |  |
Newly issued price (in dollars per share) | $ 9.2 | $ 9.2 |  |
Threshold minimum percentage of gross proceeds on total equity proceeds (as a percent) | 60.00% | 60.00% |  |
Adjustment of exercise price of warrants based on market value and newly issued price (as a percent) | 115.00% | 115.00% |  |
Threshold period for not to transfer, assign or sell any of their shares or warrants after the completion of the initial business combination | 30 days | 30 days |  |
Class A common stock |  |  |  |
Warrants |  |  |  |
Newly issued price (in dollars per share) | $ 9.2 | $ 9.2 |  |
Number of shares issuable per warrant (in shares) |  |  |  | 1
Redemption of warrants when price per share of Class A common stock equals or exceeds $18.00 |  |  |  |
Warrants |  |  |  |
Stock price trigger for redemption of warrants (in dollars per share) | $ 18 |  |  |
Redemption price per warrant (in dollars per share) |  | $ 18 |  |
Threshold consecutive trading days for redemption of warrants | 30 days | 30 days |  |
Adjustment of exercise price of warrants based on market value and newly issued price (as a percent) | 180.00% | 180.00% |  |
Redemption of warrants when price per share of Class A common stock equals or exceeds $18.00 | Class A common stock |  |  |  |
Warrants |  |  |  |
Threshold trading days for redemption of warrants |  | 20 days |  |
Threshold consecutive trading days for redemption of warrants |  | 30 days |  |
Redemption of Warrants when price per share of Class A common stock equals or exceeds $10.00 |  |  |  |
Warrants |  |  |  |
Stock price trigger for redemption of warrants (in dollars per share) | $ 10 | $ 10 |  |
Threshold number of trading days before sending notice of redemption to warrant holders | 30 days | 30 days |  |
Redemption price per warrant (in dollars per share) | $ 0.1 | $ 0.1 |  |
Threshold trading days for redemption of warrants | 20 days | 20 days |  |
Threshold consecutive trading days for redemption of warrants | 30 days | 30 days |  |
Redemption of Warrants when price per share of Class A common stock equals or exceeds $10.00 | Class A common stock |  |  |  |
Warrants |  |  |  |
Stock price trigger for redemption of warrants (in dollars per share) | $ 10 | $ 10 |  |
Redemption of Warrants when price per share of Class A common stock is less than $18.00 |  |  |  |
Warrants |  |  |  |
Redemption price per warrant (in dollars per share) | $ 18 |  |  |
Redemption of Warrants when price per share of Class A common stock is less than $18.00 | Class A common stock |  |  |  |
Warrants |  |  |  |
Threshold trading days for redemption of warrants | 20 days |  |  |
Threshold consecutive trading days for redemption of warrants | 30 days |  |  |
Public Warrants |  |  |  |
Warrants |  |  |  |
Class of warrant or right outstanding | 11,500,000 | 11,500,000 |  |
Warrants exercisable term after the completion of a business combination | 30 days | 30 days |  |
Term of warrants | 5 years | 5 years |  |
Threshold maximum period for filing registration statement after business combination | 15 days | 15 days |  |
Public Warrants | Class A common stock |  |  |  |
Warrants |  |  |  |
Number of shares issuable per warrant (in shares) |  |  | 0.1 |
Public Warrants | Redemption of warrants when price per share of Class A common stock equals or exceeds $18.00 |  |  |  |
Warrants |  |  |  |
Stock price trigger for redemption of warrants (in dollars per share) | $ 18 | $ 18 |  |
Threshold number of trading days before sending notice of redemption to warrant holders | 30 days | 30 days |  |
Redemption price per warrant (in dollars per share) | $ 0.01 | $ 0.01 |  |
Threshold trading days for redemption of warrants | 20 days | 20 days |  |
Threshold consecutive trading days for redemption of warrants | 30 days | 30 days |  |
Public Warrants | Redemption of warrants when price per share of Class A common stock equals or exceeds $18.00 | Class A common stock |  |  |  |
Warrants |  |  |  |
Stock price trigger for redemption of warrants (in dollars per share) | $ 18 | $ 18 |  |
Private placement warrants |  |  |  |
Warrants |  |  |  |
Class of warrant or right outstanding | 11,700,000 | 11,700,000 |  |

X
- Definition Percentage of adjustment of exercise price of warrants based on market value and newly issued price. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice
Namespace Prefix: | port_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Price of the entity's common stock which would be required to be attained to trigger the redemption of warrants. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger
Namespace Prefix: | port_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold number of specified consecutive trading days for stock price trigger considered for redemption of warrants. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold number of specified trading days for stock price trigger considered for redemption of warrants. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold number of trading days before sending notice of redemption to warrant holders. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDaysBeforeSendingNoticeOfRedemptionOfWarrants
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Redemption price per share or per unit of warrants or rights outstanding. + References No definition available. + Details
Name: | port_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights
Namespace Prefix: | port_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum threshold period for filing registration statement after business combination, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | port_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The maximum threshold period for registration statement to become effective after business combination, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | port_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The aggregate gross proceeds as a threshold minimum percentage of total equity proceeds. + References No definition available. + Details
Name: | port_PercentageOfGrossProceedsOnTotalEquityProceedsThresholdMinimum
Namespace Prefix: | port_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition The threshold period for not to transfer, assign or sell any of the shares or warrants, after the completion of the initial business combination. + References No definition available. + Details
Name: | port_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Threshold trading days for calculating Market Value of shares. + References No definition available. + Details
Name: | port_ThresholdTradingDaysForCalculatingMarketValue
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition The warrants exercisable term after the completion of a business combination, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | port_WarrantsAndRightsOutstandingExercisableTermAfterBusinessCombination
Namespace Prefix: | port_
Data Type: | xbrli:durationItemType
Balance Type: | na
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 No definition available. + Details
Name: | us-gaap_ClassOfWarrantOrRightLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of securities into which each warrant or right may be converted. For example, but not limited to, each warrant may be converted into two shares. + References No definition available. + Details
Name: | us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of warrants or rights outstanding. + References No definition available. + Details
Name: | us-gaap_ClassOfWarrantOrRightOutstanding
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Price of a single share of a number of saleable stocks of a company. + References No definition available. + Details
Name: | us-gaap_SharePrice
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2)(i) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 820 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (bbb)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482106/820-10-50-2 + Details
Name: | us-gaap_WarrantsAndRightsOutstandingTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=port_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceedsUsdEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=port_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceedsUsdTenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementScenarioAxis=port_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockIsLessThanUsdEighteenMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=port_PublicWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ClassOfWarrantOrRightAxis=port_PrivatePlacementWarrantsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |