Summary of Significant Accounting Policies (Schedule of Intangible Assets and Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Real Estate Properties [Line Items]
Intangible lease liabilities (below market in-place leases)	$ 63,205	$ 84,292
Above-Market In-Place Lease Assets
Real Estate Properties [Line Items]
Intangible lease assets	2,227	2,082
In-Place Lease Valuation
Real Estate Properties [Line Items]
Intangible lease assets	159,643	157,101
Intangible Lease Origination Costs (included as component of Deferred Lease Costs)
Real Estate Properties [Line Items]
Intangible lease assets	$ 254,856	$ 256,627

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 928
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473545&loc=d3e61844-108004

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant