Schedule of investment in real estates (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Real Estate Properties [Line Items]
Investments in real estate	$ 14,844,038	$ 11,913,693
North America
Real Estate Properties [Line Items]
Land (related to rental properties)	2,225,785	1,625,349
Buildings and building improvements	11,775,132	9,986,635
Other improvements	1,277,862	976,627
Rental properties	15,278,779	12,588,611
Development and redevelopment projects	2,057,084	1,460,814
Future development projects	182,746	98,802
Gross investments in real estate	17,518,609	14,148,227
Less: accumulated depreciation	(2,704,657)	(2,263,797)
Investments in real estate	14,813,952	11,884,430
Asia
Real Estate Properties [Line Items]
Investments in real estate	$ 30,086	$ 29,263

Carrying amount as of the balance sheet date of improvements not otherwise specified in the existing taxonomy.

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The current amount of expenditures for a real estate project that has not yet been completed.

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Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Carrying amount of land available for development.

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The cumulative amount of depreciation for real estate property held for investment purposes.

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Amount of real estate investment property 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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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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Carrying amount of income producing properties held for rental.

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