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The number of partner's interest acquired.

No definition available.

Name:	spg_NumberOfPartnersInterestAcquired
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The number of real estate properties in which additional interests were acquired during the period.

No definition available.

Name:	spg_NumberOfRealEstatePropertiesAcquired
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This element represents the number of real estate properties that were disposed of during the period.

No definition available.

Name:	spg_NumberOfRealEstatePropertiesDisposed
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Area of a real estate property.

No definition available.

Name:	us-gaap_AreaOfRealEstateProperty
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Data Type:	num:areaItemType
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Period Type:	instant

Number of shares of equity interests issued or issuable to acquire entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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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.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of long-term debt due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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Percentage of voting equity interests acquired in a business combination achieved in stages, including equity interests in the acquiree held by the acquirer immediately before the acquisition date and acquired at the acquisition date.

No definition available.

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Data Type:	num:percentItemType
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In a business combination achieved in stages, this element represents the amount of net gain (loss) recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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-Name Accounting Standards Codification

-Glossary Investing Activities

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Balance Type:	credit
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.

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Data Type:	xbrli:stringItemType
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Period Type:	duration

Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

No definition available.

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Data Type:	num:percentItemType
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Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Period Type:	duration

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Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DiscontinuedOperationsDisposedOfByMeansOtherThanSaleSpinoffMember
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Name:	us-gaap_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=spg_AshfordDesignerOutletsMember
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Data Type:	na
Balance Type:
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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_BusinessAcquisitionAxis=spg_JerseyGardensAndUniversityParkVillageMember
Namespace Prefix:
Data Type:	na
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Namespace Prefix:
Data Type:	na
Balance Type:
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Name:	us-gaap_BusinessAcquisitionAxis=spg_PortfolioOfTenPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_RealEstatePropertiesAxis=us-gaap_UnconsolidatedPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_MortgageLoansOnRealEstateDescriptionTypeOfPropertyAxis=spg_RetailPropertiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_DisposalGroupClassificationAxis=us-gaap_DisposalGroupDisposedOfBySaleNotDiscontinuedOperationsMember
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