Consolidated Balance Sheets (Parenthetical) - $ / shares shares in Thousands	Dec. 31, 2020	Dec. 31, 2019
Common Shares of Beneficial Interest - par value, $.03 per share; shares authorized: 275,000; shares issued and outstanding:128,103 in 2020 and 128,702 in 2019
Common Shares of Beneficial Interest; par value (dollars per share)	$ 0.03	$ 0.03
Common Shares of Beneficial Interest - shares authorized (shares)	275,000	275,000
Common Shares of Beneficial Interest - shares issued (shares)	127,313	128,702
Common Shares of Beneficial Interest - shares outstanding (shares)	127,313	128,702

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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