Amount of debt as of the reporting date.

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Amount of total gross properties and lease intangibles acquired at the acquisition date.

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The number of equity interests in unconsolidated commercial real estate properties.

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Represents the number of properties acquired that closed during the reporting period.

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The number of retail properties.

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The number of square feet properties.

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Area of a real estate property.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Cash received for the sale of real estate that is not part of an investing activity during the current period.

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Properties - Narrative (Details) ft² in Millions, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Sep. 30, 2017 ft² property	Mar. 31, 2022 USD ($) property	Mar. 31, 2021 USD ($)	Dec. 31, 2016 ft² Item
Operating properties \| Montgomery Alabama \| Commercial and Residential Lending Segment
Real Estate Properties [Line Items]
Proceeds from sale of operating properties		$ 114.8	$ 31.2
Gain on sale of property		86.6	$ 17.7
Medical Office Portfolio
Real Estate Properties [Line Items]
Number of acquired properties closed \| Item				34
Area of property \| ft²				1.9
Total gross properties and lease intangibles		762.6
Debt		594.9
Master Lease Portfolio
Real Estate Properties [Line Items]
Total gross properties and lease intangibles		343.8
Debt		193.1
Number of retail properties acquired \| property	16
Number of square feet of properties \| ft²	1.9
Term of master lease agreements	24 years 7 months 6 days
Master Lease Portfolio \| Minimum \| Retail Properties \| Geographic Concentration Risk \| Utah, Florida, Texas and Minnesota
Real Estate Properties [Line Items]
Concentration risk (as a percent)	50.00%
REIS Equity Portfolio
Real Estate Properties [Line Items]
Total gross properties and lease intangibles		198.6
Debt		$ 138.6
Number of retail properties acquired \| property		12
Number of equity interests in unconsolidated commercial real estate properties \| property		1
REIS Equity Portfolio \| Operating properties
Real Estate Properties [Line Items]
Proceeds from sale of operating properties		$ 34.5
Gain on sale of property		$ 11.7