Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accounts receivable, allowance	$ 284	$ 1,653
Accrued rent receivable, allowance	$ 11,009	$ 11,266
Common Stock, Par or Stated Value Per Share (USD per share)	$ 0.01	$ 0.01
Common Stock, Shares Authorized	400,000,000	400,000,000
Common Stock, Shares, Issued and Outstanding	176,197,883	176,873,324
Common Shares in Grantor Trust, Issued and Outstanding	1,113,450	977,120
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Accounts receivable, allowance	$ 284	$ 1,653
Accrued rent receivable, allowance	$ 11,009	$ 11,266
Redeemable Limited Partnership Units Issued and Outstanding	981,626	982,871
General Partners' Capital Account, Units Issued and Outstanding	176,197,883	176,873,324