Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Accounts receivable, allowance	$ 284	$ 284
Accrued rent receivable, allowance	$ 7,484	$ 7,691
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	400,000,000	400,000,000
Common stock, shares issued (in shares)	170,965,987	176,480,095
Common stock, shares outstanding (in shares)	170,965,987	176,480,095
Common shares in grantor trust, issued and outstanding (in shares)	1,117,783	1,105,542
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Accounts receivable, allowance	$ 284	$ 284
Accrued rent receivable, allowance	$ 7,484	$ 7,691
Redeemable limited partnership units issued (in units)	981,634	981,634
Redeemable limited partnership units outstanding (in units)	981,634	981,634
General partners' capital account, units issued (in units)	170,965,987	176,480,095
General partners' capital account, units outstanding (in units)	170,965,987	176,480,095

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Common shares in grantor trust issued and outstanding.

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Face amount or stated value per share of common stock.

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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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