Other Noncontrolling Interests (Details) - Other Noncontrolling Interest	Dec. 31, 2017 joint_venture
Noncontrolling Interest [Line Items]
Number of consolidated joint ventures	2
Minimum
Noncontrolling Interest [Line Items]
Noncontrolling interest in operating partnership (as a percent)	5.00%

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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