Real Estate Investments (Details) $ in Thousands	3 Months Ended
Mar. 31, 2021 USD ($) ft² item site state property	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($) ft²
Real Estate Investments
Number of Real Estate Properties	1,213		1,129
Land Subject to Ground Leases \| ft²	24,200,000		22,700,000
Net Real Estate Investments	$ 3,575,025		$ 3,304,179
Retail Net Lease Assets Purchased \| item	86
Payments to Acquire Property, Plant, and Equipment	$ 387,900
Number Of States Properties Located \| state	25
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life (in year)	12 years 10 months 24 days
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Land	$ 126,700
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Buildings	168,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill	84,200
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets	$ 8,800
Number Of Development And Partner Capital Solutions Projects Completed \| site	1
Number of Development and Partner Capital Solutions Projects Construction \| site	3
Number of properties sold \| property	3
Proceeds from Sale of Real Estate	$ 8,400
Gains on Sales of Investment Real Estate	2,900
Provision for impairment	$ 0	$ 0

The number of Development And Partner Capital Solutions Projects completed during reporting period.

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The number of Development and Partner Capital Solutions projects being constructed or beginning construction.

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Represents the number of properties sold.

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Number of states in which properties of company located

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Represents number of retail net lease assets purchased by company.

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Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of facility held for productive use including, but not limited to, office, production, storage and distribution facilities, acquired at the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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Amount of real estate acquired, at the acquisition date.

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Amount of other assets expected to be realized or consumed after one year or the normal operating cycle, if longer, acquired at the acquisition date.

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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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The aggregate amount of write-downs for impairments recognized during the period for long lived assets held for use (including those held for disposal by means other than sale).

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Area of land subject to a ground lease.

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

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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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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Amount of real estate investment property, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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