Real Estate Asset Acquisition - Waltham Woods Corporate Center (Details) - 880 & 890 Winter Street [Member] $ in Thousands	Aug. 27, 2019 USD ($)
Business Acquisition [Line Items]
Land	$ 31,376
Building and improvements	57,922
Tenant improvements	6,024
Net assets acquired	105,970
In-place lease intangibles [Member]
Business Acquisition [Line Items]
Lease intangibles	11,494
Above-market lease intangibles [Member]
Business Acquisition [Line Items]
Lease intangibles	246
Below-market lease intangibles [Member]
Business Acquisition [Line Items]
Lease intangibles	$ (1,092)

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Amount of facility held for productive use including, but not limited to, office, production, storage and distribution facilities, acquired at the acquisition date.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of real estate acquired, at the acquisition date.

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Amount recognized as of the acquisition date for the identifiable assets acquired in excess of (less than) the aggregate liabilities assumed.

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