Investments in Unconsolidated Entities - Asian Joint Ventures (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Investment in Unconsolidated Entities
Equity investment	$ 2,302,833	$ 2,266,483
Japan \| Mitsubishi Estate Co., Ltd. \| Premium Outlets
Investment in Unconsolidated Entities
Ownership percentage	40.00%
Equity investment	$ 221,600	230,300
South Korea \| Shinsegae International Co \| Premium Outlets
Investment in Unconsolidated Entities
Ownership percentage	50.00%
Equity investment	$ 155,200	$ 149,100

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66011266&loc=d3e33918-111571

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66022249&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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+ References

No definition available.

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