Investments in Real Estate - Properties with Existing Leases (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) property	Dec. 31, 2018 USD ($) property	Dec. 31, 2017 USD ($)
Investments in real estate properties
Value of properties acquired during the period	$ 3,715.2	$ 1,797.5
Number of properties acquired during the period \| property	789	764
Rental Revenue
Investments in real estate properties
Amortization of above and below market Leases	$ 21.7	$ 16.9	$ 14.0
In-Place Leases
Investments in real estate properties
Depreciation and amortization expense	112.0	106.6	$ 104.8
Real Estate Investment
Investments in real estate properties
Value of properties acquired during the period	3,700.0	1,800.0
Real Estate Investment \| Properties with existing leases \| In-Place Leases
Investments in real estate properties
Value of properties acquired during the period	$ 2,720.0	$ 425.5
Number of properties acquired during the period \| property	575	205

The number of new properties and properties under development in which the entity invested during the period.

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- Definition

Real Estate Property Investments, Value Of Properties Acquired

+ References

No definition available.

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- Definition

Amount of non-cash amortization of intangible asset (liability) for above and below market leases.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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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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