Derivative Instruments - Summary of Effects of Derivative Financial Instruments on Consolidated Statements of Operations (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Derivative [Line Items]
Gain (loss) recognized in other comprehensive income	$ (1,145,252)	$ 207,681	$ (2,667,733)	$ 1,482,567
Gain (loss) reclassified from other comprehensive income	52,035	(462,289)	125,779	(938,663)
Amount of Gain or (Loss) Recognized in Income on Derivative		(2,530)	(195,176)	(2,530)
Interest Rate Swap
Derivative [Line Items]
Gain (loss) recognized in other comprehensive income	(110,434)	216,938	(1,477,659)	1,470,654
Gain (loss) reclassified from other comprehensive income	$ 2,519	(375,289)	1,340	(764,662)
Amount of Gain or (Loss) Recognized in Income on Derivative		$ (2,530)	$ (305,981)	$ (2,530)
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]		Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating
Interest Rate Cap
Derivative [Line Items]
Gain (loss) reclassified from other comprehensive income	$ 49,516	$ (87,000)	$ 124,439	$ (174,001)
Amount of Gain or (Loss) Recognized in Income on Derivative			$ 110,805
Derivative Instrument, Gain (Loss) Reclassified from AOCI into Income, Effective Portion, Statement of Income or Comprehensive Income [Extensible Enumeration]	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating	Interest Expense, Operating and Nonoperating
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]			Interest Expense, Operating and Nonoperating
Foreign Currency Option
Derivative [Line Items]
Gain (loss) recognized in other comprehensive income	$ (1,034,818)	$ (9,257)	$ (1,190,074)	$ 11,913

Derivative instruments, gain (loss) recognized in other comprehensive income.

No definition available.

Name:	sstvi_DerivativeInstrumentsGainLossRecognizedInOtherComprehensiveIncome
Namespace Prefix:	sstvi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

+ Details

Name:	us-gaap_DerivativeGainLossOnDerivativeNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from derivative.

+ References

+ Details

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

- Definition

Indicates line item in statement of income or comprehensive income that includes gain (loss) from effective portion of derivative instrument reclassified from accumulated other comprehensive income (AOCI) into income.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4D
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4D

+ Details

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

- Definition

The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 4D
-Subparagraph (b)
-SubTopic 10
-Topic 815
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4D

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4C
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4C

+ Details

Name:	us-gaap_DerivativeInstrumentsGainLossReclassifiedFromAccumulatedOCIIntoIncomeEffectivePortionNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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 815
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480237/815-40-50-5

+ Details

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

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateCapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForeignExchangeOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: