Joint venture interest in acquired business.

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Number of joint venture properties.

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Number of joint ventures acquired.

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Number of properties interested.

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Number of wholly owned properties.

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Organization And Basis Of Presentation [Line Items]

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Percent of contractual rental income collected.

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Percent of tenant contractual rental income collected.

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Area of a real estate property.

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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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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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The number of states the entity operates in as of the balance sheet date.

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Organization - Additional Information (Detail) $ in Thousands, ft² in Millions		3 Months Ended
	Jul. 07, 2015 USD ($) JointVenture	Mar. 31, 2021 USD ($) ft² Property State	Mar. 31, 2020 USD ($)
Organization And Basis Of Presentation [Line Items]
Number of properties interested in the portfolio \| Property		179
Number of states in properties located \| State		41
Net cash (used in) provided by operating activities		$ 12,110	$ 10,200
Net cash (used in) provided by investing activities		$ (7,528)	$ 31,024
COVID-19 Pandemic [Member]
Organization And Basis Of Presentation [Line Items]
Expected future rent, description		Company had collected 97% of
Net cash (used in) provided by operating activities		$ 12,100
Net cash (used in) provided by investing activities		$ 44,200
COVID-19 Pandemic [Member] \| March 2021 [Member]
Organization And Basis Of Presentation [Line Items]
Percent of contractual rental income collected		97.00%
Percent of tenant contractual rental income collected		2.00%
Sears Holdings Corporation [Member]
Organization And Basis Of Presentation [Line Items]
Business acquisition fair value, purchase price	$ 2,700,000
Interests in joint ventures acquired	50.00%
Number of joint venture acquired \| JointVenture	3
Wholly Owned Properties [Member] \| Holdco Master Lease [Member]
Organization And Basis Of Presentation [Line Items]
Number of wholly owned properties \| Property		5
Real Estate Investment Trust [Member]
Organization And Basis Of Presentation [Line Items]
Area of real estate property (in square feet) \| ft²		26.0
Real Estate Investment Trust [Member] \| Wholly Owned Properties [Member]
Organization And Basis Of Presentation [Line Items]
Area of real estate property (in square feet) \| ft²		24.1
Number of wholly owned properties \| Property		154
Number of states in properties located \| State		41
Real Estate Investment Trust [Member] \| Unconsolidated Properties [Member]
Organization And Basis Of Presentation [Line Items]
Area of real estate property (in square feet) \| ft²		1.9
Number of states in properties located \| State		13
Number of properties \| Property		25