Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

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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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Subsequent Events - Additional Information (Details) $ in Thousands			12 Months Ended
	Feb. 13, 2020 USD ($)	Jan. 09, 2020 USD ($)	Dec. 31, 2019 USD ($) property	Dec. 31, 2018 USD ($)	Feb. 07, 2020 USD ($)	Jan. 31, 2020 property	Jan. 17, 2020 USD ($)	Mar. 28, 2018 USD ($)	Nov. 16, 2017 USD ($)
Subsequent Event [Line Items]
Number of retail properties \| property			186
Purchase Price			$ 324,339	$ 186,463
Mezzanine loan to joint venture partner			226,301
Soho Acquisitions \| New York, NY
Subsequent Event [Line Items]
Purchase Price			$ 122,000
Subsequent Event \| Venture Partner’s Interest \| Georgetown Portfolio
Subsequent Event [Line Items]
Mezzanine loan to joint venture partner					$ 5,000
Subsequent Event \| New York, NY
Subsequent Event [Line Items]
Equity method investments							$ 54,000
Core Portfolio
Subsequent Event [Line Items]
Number of retail properties \| property			129
Purchase Price			$ 146,435	1,337
Equity method investments			225,907	231,432				$ 22,300	$ 61,600
Core Portfolio \| Georgetown Portfolio
Subsequent Event [Line Items]
Equity method investments			$ 4,498	$ 4,653
Core Portfolio \| Subsequent Event
Subsequent Event [Line Items]
Number of retail properties \| property						2
Core Portfolio \| Subsequent Event \| Soho Acquisitions \| 37, Green Street, New York
Subsequent Event [Line Items]
Purchase Price		$ 15,400
Core Portfolio \| Subsequent Event \| Chicago Illinois Acquisitions \| 917 West Armitage Avenue
Subsequent Event [Line Items]
Purchase Price	$ 3,500