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.

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-Publisher FASB
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-Topic 230
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Summary of Significant Accounting Policies - Future Amortization Expense Related to Deferred Leasing Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
In-Place Leases and Tenant Relationships
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	$ 8,201	$ 6,303	$ 6,267
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2021	4,210
2022	3,717
2023	3,283
2024	2,562
2025	1,996
Above and Below Market Leases
Finite-Lived Intangible Assets [Line Items]
Amortization of Intangible Assets	1,962	$ 1,281	$ 1,095
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
2021	1,443
2022	1,353
2023	1,101
2024	1,120
2025	$ 1,029