Real Estate - Real Estate Under Development and Construction in Progress - Additional Information (Details) - property	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2018
Cortlandt Crossing \| Fund III
Property, Plant and Equipment [Line Items]
Number of projects put into service during period	1
Core Portfolio
Property, Plant and Equipment [Line Items]
Number of projects put into service during period		1

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.

No definition available.

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Balance Type:	na
Period Type:	duration