Date of senior secured term loan agreement.

No definition available.

Name:	srg_DateOfSeniorSecuredTermLoanAgreement
Namespace Prefix:	srg_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Default interest rate on overdue amounts excess of base interest rate.

+ References

No definition available.

+ Details

Name:	srg_DefaultInterestRateOnOverdueAmountsExcessOfBaseInterestRate
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Fixed charge coverage ratio to each fiscal quarter after three years.

+ References

No definition available.

+ Details

Name:	srg_FixedChargeCoverageRatioToEachFiscalQuarterAfterThreeYears
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Fixed charge coverage ratio to each fiscal quarter for next three years.

+ References

No definition available.

+ Details

Name:	srg_FixedChargeCoverageRatioToEachFiscalQuarterForNextThreeYears
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Line of credit facility leverage ratio.

+ References

No definition available.

+ Details

Name:	srg_LineOfCreditFacilityLeverageRatio
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum net worth required for loan documentation.

+ References

No definition available.

+ Details

Name:	srg_MinimumNetWorthRequiredForLoanDocumentation
Namespace Prefix:	srg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Unencumbered fixed charge coverage ratio.

+ References

No definition available.

+ Details

Name:	srg_UnencumberedFixedChargeCoverageRatio
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Unencumbered fixed charge coverage ratio to each fiscal quarter for after three years.

+ References

No definition available.

+ Details

Name:	srg_UnencumberedFixedChargeCoverageRatioToEachFiscalQuarterAfterThreeYears
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Unencumbered fixed charge coverage ratio to each fiscal quarter for next three years.

+ References

No definition available.

+ Details

Name:	srg_UnencumberedFixedChargeCoverageRatioToEachFiscalQuarterForNextThreeYears
Namespace Prefix:	srg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

- Definition

Date the credit facility terminates, in CCYY-MM-DD format.

+ References

+ Details

Name:	us-gaap_LineOfCreditFacilityExpirationDate1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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

- Details

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

- Details

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

- Details

Name:	us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	us-gaap_DebtInstrumentAxis=srg_IncrementalFundingFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Subsequent Events - Additional Information (Detail) - USD ($)		6 Months Ended
	Jul. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Unsecured term loan, net		$ 144,111,000	$ 143,210,000
Debt instrument, base annual interest rate		6.50%
Term Loan Facility [Member] \| Berkshire Hathaway [Member]
Subsequent Event [Line Items]
Line of credit, maturity date		Jul. 31, 2023
Subsequent Event [Member] \| Term Loan Facility [Member] \| Berkshire Hathaway [Member]
Subsequent Event [Line Items]
Date of senior secured term loan agreement	Jul. 31, 2018
Unsecured term loan, net	$ 2,000,000,000
Default interest rate on overdue amounts excess of base interest rate	2.00%
Minimum net worth required for loan documentation	$ 1,200,000,000
Subsequent Event [Member] \| Term Loan Facility [Member] \| Berkshire Hathaway [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Unencumbered fixed charge coverage ratio	60.00%
Maximum leverage ratio	65.00%
Subsequent Event [Member] \| Term Loan Facility [Member] \| Berkshire Hathaway [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Fixed charge coverage ratio for each fiscal quarter till June 30, 2021	1.00%
Fixed charge coverage ratio for each fiscal quarter after June 30, 2021	1.20%
Unencumbered fixed charge coverage ratio for each fiscal quarter till June 30, 2021	1.05%
Unencumbered fixed charge coverage ratio to each fiscal quarter after June 30, 2021	1.30%
Subsequent Event [Member] \| Term Loan Facility [Member] \| Berkshire Hathaway [Member] \| Initial Funding [Member]
Subsequent Event [Line Items]
Unsecured term loan, net	$ 1,600,000,000
Debt instrument, base annual interest rate	7.00%
Subsequent Event [Member] \| Term Loan Facility [Member] \| Berkshire Hathaway [Member] \| Incremental Funding Facility [Member]
Subsequent Event [Line Items]
Unsecured term loan, net	$ 400,000,000
Debt instrument, base annual interest rate	1.00%