Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accounts receivable, allowance	$ 284	$ 1,653
Accrued rent receivable, allowance	$ 7,691	$ 11,266
Common stock, par or stated value per share (usd per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized (in shares)	400,000,000	400,000,000
Common Stock, Shares, Issued (in shares)	176,480,095	176,873,324
Common Stock, Shares, Outstanding (in shares)	176,480,095	176,873,324
Common Shares in Grantor Trust, Issued and Outstanding (in shares)	1,105,542	977,120
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Accounts receivable, allowance	$ 284	$ 1,653
Accrued rent receivable, allowance	$ 7,691	$ 11,266
Temporary Equity, Shares Issued	981,634	982,871
Redeemable Limited Partnership Units Issued and Outstanding (in units)	981,634	982,871
General Partners' Capital Account, Units Issued (in units)	176,480,095	176,873,324
General Partners' Capital Account, Units Issued and Outstanding (in units)	176,480,095	176,873,324

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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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