Name:	sret_AcquisitionFeesAndExpensesNetPercentage
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Amounts owed for acquisition fees to Advisor

No definition available.

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

Represents the unpaid reimbursable operating costs owed to Advisor.

No definition available.

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

Advisory disposition fee sale of cap amount

No definition available.

Name:	sret_AdvisoryDispositionFeeSaleOfCapAmount
Namespace Prefix:	sret_
Data Type:	srt-types:perUnitItemType
Balance Type:	na
Period Type:	duration

The percentage of the sales price of each investment, charged for services in the effort to sell any investment.

No definition available.

Name:	sret_AdvisoryDispositionFeeSaleOfInvestments
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Fees incurred to cover the office facilities, equipment, supplies and staff required to manage the Real Estate Investment Trust (REIT).

No definition available.

Name:	sret_AdvisoryManagementFees
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amounts owed for management fees to Advisor.

No definition available.

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

The percentage of the purchase price of each property acquired, charged for services in investigating and negotiating acquisitions of investments.

No definition available.

Name:	sret_BusinessAcquisitionPurchasePriceAllocationAcquisitionFees
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The cap per acquisition for acquisition fees charged by the Advisor.

No definition available.

Name:	sret_CriteriaAcquisitionFees
Namespace Prefix:	sret_
Data Type:	srt-types:perUnitItemType
Balance Type:	na
Period Type:	duration

The maximum percentage of total project costs, charged as development fee.

No definition available.

Name:	sret_DevelopmentFeePercentage
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Represents the lower or upper end of the range of development fees that may be incurred based on the total project costs sliding scale.

No definition available.

Name:	sret_DevelopmentFeeRangeValue
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Total development fees incurred with our Advisor.

No definition available.

Name:	sret_DevelopmentFees
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amounts of outstanding development fees as a part of 10% hold back.

No definition available.

Name:	sret_DevelopmentFeesHoldBackOutstanding
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amounts owed for development fees to Advisor.

No definition available.

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

Total disposition fees incurred with our Advisor.

No definition available.

Name:	sret_DispositionFees
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amounts owed for disposition fees to Advisor.

No definition available.

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

The amount of finance fee capped per loan.

No definition available.

Name:	sret_FinanceFeeCappedPerLoan
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The percentage of all amounts made available pursuant to any loan, refinancing (excluding rate and/or term modifications of an existing loan with the same lender), line of credit or other credit facility, charged for services related to the financing.

No definition available.

Name:	sret_FinancingFee
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Total financing fees incurred with our Advisor for loan financing and refinancing activities.

No definition available.

Name:	sret_FinancingFeesForLoanFinancingAndRefinancingActivities
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amounts owed for financing fees to Advisor

No definition available.

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

Management Fee Percentage Of Assets

No definition available.

Name:	sret_ManagementFeePercentageOfAssets
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Maximum Management Fee Payable In Cash Or Common Shares

No definition available.

Name:	sret_MaximumManagementFeePayableInCashOrCommonShares
Namespace Prefix:	sret_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Number Of Paid Employees

No definition available.

Name:	sret_NumberOfPaidEmployees
Namespace Prefix:	sret_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

The number of operating partnership (OP) units issued in connection with acquisitions.

No definition available.

Name:	sret_OperatingPartnershipUnitsIssuedInConnectionWithAcquisitionUnits
Namespace Prefix:	sret_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

The value of operating partnership (OP) units issued in connection with acquisitions.

No definition available.

Name:	sret_OperatingPartnershipUnitsIssuedInConnectionWithAcquisitionValue
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The amount of other operational liabilities outstanding as on the balance sheet date.

No definition available.

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

Percentage of outstanding development fees as a part of hold back.

No definition available.

Name:	sret_PercentageOfDevelopmentFeesHoldBack
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the percentage of project management fee.

No definition available.

Name:	sret_PercentageOfProjectManagementFee
Namespace Prefix:	sret_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

The amount of project management fees incurred during period.

No definition available.

Name:	sret_ProjectManagementFee
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The carrying amount as of the balance sheet date of project management fees payable.

No definition available.

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

Total real estate commissions incurred with a related party.

No definition available.

Name:	sret_RealEstateCommissions
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amounts owed to related party for real estate commissions.

No definition available.

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

Amount of reimbursement made to advisor regarding to operating costs which is including of travel and meals, legal and office supplies.

No definition available.

Name:	sret_ReimbursementOfOperatingCosts
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

The total project cost used to calculate the development fee.

No definition available.

Name:	sret_TotalProjectCostUsedToCalculateDevelopmentFee
Namespace Prefix:	sret_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI http://asc.fasb.org/extlink&oid=118952077&loc=SL77927221-108306

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=119202524&loc=SL77919372-209981

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

A description of what the property management fee percentage is taken against to determine the fee charged to clients.

No definition available.

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

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.

No definition available.

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

Name:	us-gaap_RelatedPartyTransactionAxis=sret_AdvisoryAgreementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

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

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

Name:	sret_DevelopmentFeeRangeAxis=sret_RangeOneMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	sret_DevelopmentFeeRangeAxis=sret_RangeTwoMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	sret_DevelopmentFeeRangeAxis=sret_RangeThreeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	sret_DevelopmentFeeRangeAxis=sret_RangeFourMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	sret_DevelopmentFeeRangeAxis=sret_RangeFiveMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sret_SterlingManagementLlcMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sret_GoldmarkPropertyManagementMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=sret_GoldmarkSchlossmanCommercialRealEstateServicesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: