Property (Schedule Of Property) (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Real Estate [Abstract]
Land	$ 957,362	$ 1,068,022
Land held for development	57,736	69,205
Land under development	53,570	48,985
Buildings and improvements	3,045,537	3,232,074
Construction in-progress	131,309	80,573
Total	$ 4,245,514	$ 4,498,859

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

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- Definition

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

+ References

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Aggregate of the carrying amounts as of the balance sheet date of investments in building and building improvements.

+ References

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

+ References

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- Definition

Carrying amount of land available for development.

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No definition available.

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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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