Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Disaggregation of Revenue [Line Items]
Lease revenues	$ 48,904	$ 44,099	$ 103,315	$ 96,085
Rental revenues	51,388	45,478	107,541	99,588
Parking revenue
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	1,212	636	2,008	1,940
Tenant services
Disaggregation of Revenue [Line Items]
Revenue from contract with customer	$ 1,272	$ 743	$ 2,218	$ 1,563

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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+ Details

- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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