Debt - Summary of Outstanding Debt (Parenthetical) (Details)	Mar. 31, 2018 USD ($)
1633 Broadway [Member] \| Mortgages and Notes Payable with Variable Rate [Member]
Debt Instrument [Line Items]
Additional Borrowing Capacity Subject To Performance Hurdles	$ 200,000,000

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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