Variable Interest Entities ("VIEs") - Summary of Investments in Unconsolidated Real Estate Funds and Maximum Risk of Loss from Investments (Parenthetical) (Details) $ in Thousands	Jun. 30, 2019 USD ($)
Variable Interest Entity [Line Items]
Due from Affiliates	$ 170,000
Fund X [Member]
Variable Interest Entity [Line Items]
Due from Affiliates	$ 170,000

For an unclassified balance sheet, amount of receivables due from an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant