Real Estate - Schedule of Acquisitions and Conversions (Parenthetical) (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2019 USD ($) property	Dec. 31, 2018 USD ($)
Business Acquisition [Line Items]
Aggregate purchase price	$ 140,512	$ 186,463
Soho Portfolio \| New York, NY
Business Acquisition [Line Items]
Number of real estate properties held by Acquiree \| property	6
Aggregate purchase price	$ 96,000

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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