Identified Intangible Assets and Liabilities - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Below Market Leases Net Of Above Market Leases
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 16,878	$ 19,830	$ 38,573
Other Identified Intangible Assets
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ (6,507)	$ (8,666)	$ (18,018)

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
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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