The number of properties owned via an International joint venture.

No definition available.

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- Definition

The number of properties owned via a joint venture in which daily operations are managed by groups other than the entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The number of properties owned via a joint venture in which daily operations are managed by the entity.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The number of properties owned via a joint venture and accounted for using the equity method of accounting.

+ References

No definition available.

+ Details

Name:	simon_JointVenturePropertiesNumber
Namespace Prefix:	simon_
Data Type:	xbrli:integerItemType
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- References

No definition available.

+ Details

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- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- 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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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Basis of Presentation (Details) - property	Jun. 30, 2015	Dec. 31, 2014	Jun. 30, 2014
Real estate properties
Total number of joint venture properties	80
Number of joint venture properties managed by the entity	58
Number of International joint venture properties	19
Number of joint venture properties managed by others	22
European Joint Venture \| Premium Outlets
Real estate properties
Number of properties	5
Simon Property Group, Inc
Ownership interest:
Ownership percentage in the Operating Partnership	85.70%	85.50%
Simon Property Group, Inc \| Weighted average
Ownership interest:
Ownership percentage in the Operating Partnership	85.60%		85.50%
Wholly owned properties
Real estate properties
Number of properties	135
Partially owned properties
Real estate properties
Number of properties	13