Business and Organization - Narratives (Details) ft² in Millions	12 Months Ended
Dec. 31, 2020 ft² property tenant	Dec. 31, 2019 property
Real Estate
Real Estate Properties
Number of real estate properties (property)	1,243
Square footage of real estate properties (sqft) \| ft²	144.0
Number of tenants (tenant) \| tenant	350
Operating lease term (in years)	10 years 7 months 6 days
Occupancy rate (percent)	98.50%
Real Estate \| Operating Properties
Real Estate Properties
Number of real estate properties (property)	20
Square footage of real estate properties (sqft) \| ft²	1.4
Real Estate \| Self Storage
Real Estate Properties
Number of real estate properties (property)	19
Real Estate \| Hotel
Real Estate Properties
Number of real estate properties (property)	1	2
Investment Management \| Operating Properties \| Affiliated Entity \| Managed Programs
Real Estate Properties
Number of real estate properties (property)	69
Square footage of real estate properties (sqft) \| ft²	5.6
Investment Management \| Operating Properties \| Affiliated Entity \| Managed Programs \| Built to suit
Real Estate Properties
Number of real estate properties (property)	10
Investment Management \| Net-lease properties \| Affiliated Entity \| Managed Programs
Real Estate Properties
Number of real estate properties (property)	53
Square footage of real estate properties (sqft) \| ft²	10.7
Number of tenants (tenant) \| tenant	65
Occupancy rate (percent)	98.70%

Area of a real estate property.

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=121576215&loc=SL77919359-209981

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

The number of tenants occupying the real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

The occupancy rate of our owned real estate properties as of the balance sheet date.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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