The percentage of asset coverage ratio.

No definition available.

Name:	star_AssetCoverageRatio
Namespace Prefix:	star_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Additional percentage points added to the stated interest rate or spread upon occurrence of an event of default under the terms of the debt instrument.

+ References

No definition available.

+ Details

Name:	star_DebtInstrumentIncreaseInSpreadUponDefaultPercentage
Namespace Prefix:	star_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Debt instrument, term of variable rate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

Name:	star_DebtInstrumentTermOfVariableRate
Namespace Prefix:	star_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The percentage of estimated total annualized cost of capital.

+ References

No definition available.

+ Details

Name:	star_LineOfCreditFacilityAnnualizedCostOfCapitalEstimatedPercentage
Namespace Prefix:	star_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts can be increased currently outstanding under the facility.

+ References

No definition available.

+ Details

Name:	star_LineOfCreditFacilityMaximumBorrowingCapacityCanBeIncreased
Namespace Prefix:	star_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum fixed interest rate per annum after the credit rating event occurs.

+ References

No definition available.

+ Details

Name:	star_MinimumInterestRateAfterCreditRatingEvent
Namespace Prefix:	star_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
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-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in YYYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_DebtInstrumentMaturityDate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Indicates type of variable interest rate on debt instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 470
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477734/942-470-50-3

+ Details

Name:	us-gaap_DebtInstrumentVariableInterestRateTypeExtensibleEnumeration
Namespace Prefix:	us-gaap_
Data Type:	enum2:enumerationSetItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(b))
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-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (SX 210.5-02(19)(b))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

Name:	us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_SterlingNationalBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_WebsterBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_DimeCommunityBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_FirstFoundationBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_WoodforestNationalBankMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LineOfCreditFacilityAxis=star_PeapackGladstoneBankMember
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Data Type:	na
Balance Type:
Period Type:

- Details

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Borrowings, Secured Credit Facility Commitment (Details) - USD ($)			3 Months Ended
	Jan. 02, 2026	Jun. 27, 2025	Mar. 31, 2026	Dec. 31, 2025	May 31, 2024	Sep. 16, 2022	May 06, 2022	Jan. 12, 2022	Jul. 02, 2021
Senior Notes [Member]
Credit Facility Commitment [Abstract]
Maturity date			Jan. 15, 2029
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]			us-gaap:SecuredOvernightFinancingRateSofrMember
Interest rate	3.75%
Fair value of borrowings outstanding			$ 25,000,000
Minimum interest rate after credit rating event	0.50%
Aggregate principal amount	$ 25,000,000
Senior Notes [Member] \| Minimum [Member]
Credit Facility Commitment [Abstract]
Asset coverage ratio			150.00%
Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			$ 200,000,000	$ 200,000,000	$ 200,000,000	$ 200,000,000	$ 125,000,000	$ 80,000,000
Borrowing capacity can be increased			$ 350,000,000
Maturity date			Jun. 30, 2028
Term of variable rate			3 months
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]			us-gaap:SecuredOvernightFinancingRateSofrMember
Interest rate		2.30%	2.90%
Fair value of borrowings outstanding			$ 108,400,000	122,300,000
Estimated total annualized cost of capital percentage			6.30%
Percentage of increase in spread upon default		2.00%
Sterling National Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment									$ 55,000,000
Webster Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			$ 87,500,000	67,500,000
Dime Community Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			25,000,000	25,000,000
First Foundation Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			0	20,000,000
Woodforest National Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			20,000,000	20,000,000
Peapack-Gladstone Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			17,000,000	17,000,000
Hanmai Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			15,500,000	15,500,000
Apple Bank [Member] \| Revolving Credit Facility [Member]
Credit Facility Commitment [Abstract]
Secured credit facility commitment			$ 15,000,000	$ 15,000,000