Organization (Details)	Mar. 31, 2019 state country property
U.S. and Puerto Rico
Real Estate Properties
Number of properties	206
Number of U.S. states containing property locations \| state	37
U.S. and Puerto Rico \| Malls
Real Estate Properties
Number of properties	107
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	12
Asia, Europe and Canada \| Premium and Designer Outlets
Real Estate Properties
Number of properties	28
Europe \| Klepierre
Real Estate Properties
Ownership percentage	21.60%
Number of countries \| country	16

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

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

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- Definition

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

+ References

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- Definition

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

+ References

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+ Details

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- Definition

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

+ References

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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.

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- Details

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