Identified Intangible Assets and Liabilities (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Below Market Leases Net Of Above Market Leases
Finite-Lived Intangible Assets and Liabilities
Increase to rental income	$ 3,648	$ 4,393	$ 13,054	$ 15,561
Other Identified Intangible Assets
Finite-Lived Intangible Assets and Liabilities
Amortization of intangible assets	$ 1,838	$ 1,597	$ 4,919	$ 7,077

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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