Number of regional , super regional and outlet malls.

No definition available.

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Namespace Prefix:	spg_
Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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

- Definition

The number of countries in which the entity operates as of balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

Name:	us-gaap_NumberOfRealEstateProperties
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of states the entity operates in as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
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

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:
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- Details

Name:	dei_LegalEntityAxis=spg_TaubmanRealtyGroupMember
Namespace Prefix:
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- Details

Name:	srt_StatementGeographicalAxis=spg_UnitedStatesAndPuertoRicoMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_MallsMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_PremiumOutletCentersMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_TheMillsMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_CommunityLifestyleCentersMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	srt_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_OtherShoppingCentersOrOutletCentersMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_StatementGeographicalAxis=spg_AsiaEuropeAndCanadaMember
Namespace Prefix:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

Name:	srt_StatementGeographicalAxis=srt_EuropeMember
Namespace Prefix:
Data Type:	na
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- Details

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Organization (Details)	Mar. 31, 2021 property country state	Dec. 29, 2020 property
TRG
Real Estate Properties
Ownership percentage	80.00%	80.00%
TRG \| TRG
Real Estate Properties
Number of regional, super regional and outlet malls	24	24
U.S. and Puerto Rico
Real Estate Properties
Number of properties	202
Number of U.S. states containing property locations \| state	37
U.S. and Puerto Rico \| Malls
Real Estate Properties
Number of properties	98
U.S. and Puerto Rico \| Premium Outlets
Real Estate Properties
Number of properties	69
U.S. and Puerto Rico \| The Mills
Real Estate Properties
Number of properties	14
U.S. and Puerto Rico \| Community/Lifestyle Centers
Real Estate Properties
Number of properties	4
U.S. and Puerto Rico \| Other shopping centers or outlet centers
Real Estate Properties
Number of properties	17
Asia, Europe and Canada \| Premium and Designer Outlets
Real Estate Properties
Number of properties \| state	31
Europe \| Klepierre
Real Estate Properties
Ownership percentage	22.40%
Number of countries \| country	15