Summary of Significant Accounting Policies - Noncontrolling Interests, Simon Property Group, Inc. (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Significant Accounting Policies
Limited partners' interests in the Operating Partnership	$ 400,716	$ 492,877
Nonredeemable noncontrolling interests in properties, net	6,907	7,398
Total noncontrolling interests reflected in equity	$ 407,623	$ 500,275

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(24))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.31)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(22))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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