Noncontrolling Interests (Property Partnerships) (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Noncontrolling Interest [Line Items]
Noncontrolling Interest in Limited Partnerships	$ 1,736,445	$ 1,728,689

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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