Noncontrolling Interests (Property Partnerships) (Narrative) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Noncontrolling Interest [Line Items]
Property partnerships	$ 1,590,481	$ 1,602,467

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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