DERIVATIVES AND HEDGING ACTIVITIES - Other (Details) - Interest rate swap	Jun. 30, 2025 USD ($) instrument	Dec. 31, 2024 instrument
Derivatives and Hedging Activities
Estimated amount to be reclassified over the next 12 months, as a increase to interest expense \| $	$ 2,955,295
Designated as Hedging Instrument \| Cash Flow Hedging
Derivatives and Hedging Activities
Number of instruments \| instrument	15	15

The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the remaining period of fiscal year.

No definition available.

+ Details

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Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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Balance Type:	na
Period Type:	duration

- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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Period Type:	instant

- Details

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Namespace Prefix:
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- Details

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- Details

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Namespace Prefix:
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