The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=117337397&loc=d3e23415-158514

Name:	us-gaap_GainsLossesOnSalesOfInvestmentRealEstate
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Real Estate Investments, Net - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020 USD ($) property	Sep. 30, 2019 USD ($) property	Sep. 30, 2020 USD ($) property	Sep. 30, 2019 USD ($) property	Dec. 31, 2019 property
Real Estate [Line Items]
Gain (loss) on dispositions of real estate investments \| $	$ 0	$ 6,977	$ (153)	$ 14,792
Number of real estate properties held for sale			0		0
United States
Real Estate [Line Items]
Number of real estate properties sold		33		97
United States \| Family Dollar
Real Estate [Line Items]
Number of real estate properties sold		32		94
United States \| Industrial Property
Real Estate [Line Items]
Number of real estate properties sold		1		3
UNITED KINGDOM
Real Estate [Line Items]
Number of real estate properties sold				1
Properties Sold
Real Estate [Line Items]
Number of real estate properties sold	0		0
Proceeds from dispositions of real estate investments, gross \| $			$ 53,000	$ 145,800
Gain (loss) on dispositions of real estate investments \| $		$ 7,000		$ 14,800