Related Party Transactions - Revenue and Expenses (Details) - Pillarstone OP - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Property operation and maintenance
Related Party Transaction [Line Items]
Rent	$ (225)	$ (225)	$ (672)	$ (701)
Other revenues
Related Party Transaction [Line Items]
Property management fee income	$ 142	$ 144	$ 426	$ 455

Direct costs arising from transactions with related parties who are not affiliates or joint Ventures. These costs are categorized as cost of goods sold.

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+ Details

- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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