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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	1 Months Ended	3 Months Ended		12 Months Ended
Properties - Narrative (Details) ft² in Millions	Sep. 30, 2017 ft² property	Mar. 31, 2023 USD ($) property	Mar. 31, 2022 USD ($)	Dec. 31, 2016 ft² building
Commercial and Residential Lending Segment
Real Estate Properties [Line Items]
Proceeds from sale of operating properties		$ 0	$ 0
Operating properties \| Investing and Servicing Segment
Real Estate Properties [Line Items]
Proceeds from sale of operating properties		0	34,500,000
Gain on sale of property			11,700,000
Operating properties \| Montgomery Alabama \| Commercial and Residential Lending Segment
Real Estate Properties [Line Items]
Proceeds from sale of operating properties			114,800,000
Gain on sale of property			$ 86,600,000
Medical Office Portfolio
Real Estate Properties [Line Items]
Number of acquired properties closed \| building				34
Area of property \| ft²				1.9
Total gross properties and lease intangibles		770,800,000
Debt		596,900,000
Master Lease Portfolio
Real Estate Properties [Line Items]
Total gross properties and lease intangibles		343,800,000
Debt		193,400,000
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		186,300,000
Debt		$ 129,800,000
Number of retail properties acquired \| property		10
Number of equity interests in unconsolidated commercial real estate properties \| property		1
Commercial and Residential Lending Segment Property Portfolio
Real Estate Properties [Line Items]
Total gross properties and lease intangibles		$ 481,300,000
Debt		$ 204,400,000