XML 49 R36.htm IDEA: XBRL DOCUMENT v3.25.3

LOANS HELD FOR INVESTMENT AT CARRYING VALUE - Narrative (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($) loan	Dec. 31, 2024 USD ($) loan
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Number of loans held for investments in portfolio (in loans) | loan	13	9
Loans held for investments aggregate commitments	$ 367,000,000.0	$ 190,900,000
Loans held at carrying value, outstanding principal	252,987,103	$ 132,556,289
Loans held at carrying value, outstanding principal fundings	163,100,000
Loan repayments, carrying value	$ 42,700,000
Percentage of loans held at carrying value with floating interest rates (as a percent)	96.00%	79.00%
Interest rate floor (as a percent)	4.10%
Secured Overnight Financing Rate (SOFR)
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Quoted interest rate (as a percent)	4.10%
Prime Rate
Certain Loans Acquired in Transfer Accounted for as Debt Securities Accretable Yield Movement Schedule [Line Items]
Quoted interest rate (as a percent)	7.25%
Interest rate floor (as a percent)	8.00%

X

- Definition

Aggregate commitments related to loans held for investment at carrying value.

+ References

No definition available.

+ Details

Name:	suns_LoansHeldForInvestmentAtCarryingValueAggregateCommitments
Namespace Prefix:	suns_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Loans held for investment at carrying value, outstanding principal new fundings made during the period.

+ References

No definition available.

+ Details

Name:	suns_LoansHeldForInvestmentAtCarryingValueOutstandingPrincipalNewFundings
Namespace Prefix:	suns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Loans Held For Investment, Interest Rate Floor

+ References

No definition available.

+ Details

Name:	suns_LoansHeldForInvestmentInterestRateFloor
Namespace Prefix:	suns_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Loans Held For Investment, Quoted Interest Rate

+ References

No definition available.

+ Details

Name:	suns_LoansHeldForInvestmentQuotedInterestRate
Namespace Prefix:	suns_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Total number of loans held for investments in portfolio.

+ References

No definition available.

+ Details

Name:	suns_NumberOfLoansHeldForInvestments
Namespace Prefix:	suns_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of loans held at carrying value having floating interest rates for calculation of interest.

+ References

No definition available.

+ Details

Name:	suns_PercentageOfLoansHeldWithFloatingInterestRates
Namespace Prefix:	suns_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Receivable with Imputed Interest, Loan Repayments And Amortization Payments

+ References

No definition available.

+ Details

Name:	suns_ReceivableWithImputedInterestLoanRepaymentsAndAmortizationPayments
Namespace Prefix:	suns_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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_CertainLoansAcquiredInTransferAccountedForAsDebtSecuritiesAccretableYieldMovementScheduleLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

The principal amount of the receivable or note before consideration of the discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

Name:	us-gaap_ReceivableWithImputedInterestFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_SecuredOvernightFinancingRateSofrMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_PrimeRateMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: