Earnings per common partnership unit line items.

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Noncontrolling Interest Ownership Acquired By Parent, Percent

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Repurchase program number of mirror unit of operating partnership retired for each common share repurchased.

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Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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Aggregate number of common shares reserved for future issuance.

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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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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK).

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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The number of limited partner units outstanding.

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The number of preferred units outstanding.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Price of a single share of a number of saleable stocks of a company.

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Amount of stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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The number of securities classified as temporary equity that have been sold (or granted) to the entity's shareholders. Securities issued include securities outstanding and securities held in treasury. Temporary equity is a security with redemption features that are outside the control of the issuer, is not classified as an asset or liability in conformity with GAAP, and is not mandatorily redeemable. Includes any type of security that is redeemable at a fixed or determinable price or on a fixed or determinable date or dates, is redeemable at the option of the holder, or has conditions for redemption which are not solely within the control of the issuer. If convertible, the issuer does not control the actions or events necessary to issue the maximum number of shares that could be required to be delivered under the conversion option if the holder exercises the option to convert the stock to another class of equity. If the security is a warrant or a rights issue, the warrant or rights issue is considered to be temporary equity if the issuer cannot demonstrate that it would be able to deliver upon the exercise of the option by the holder in all cases. Includes stock with put option held by ESOP and stock redeemable by holder only in the event of a change in control of the issuer.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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PARTNERS' EQUITY OF THE PARENT COMPANY - Narrative (Details) - USD ($)			12 Months Ended
	Dec. 07, 2021	Jan. 10, 2017	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Jan. 03, 2019
Earnings Per Common Partnership Unit [Line Items]
Dividends, common stock	$ 32,800,000
shares repurchased and retired (in units)			$ 0			$ 150,000,000
Repurchased and retired (in shares)				6,248,483	1,337,169
Share price (in usd per share)				$ 9.60	$ 12.92
Repurchased and retired, value				$ 59,999,000	$ 17,281,000
Common stock, par or stated value per share (in usd per share)			$ 0.01	$ 0.01
Common stock, shares authorized (in shares)			400,000,000	400,000,000
Common shares remain available for issuance (in shares)			0
Commerce Square
Earnings Per Common Partnership Unit [Line Items]
Percent of noncontrolling interest acquired			1.00%
Shelf Registration
Earnings Per Common Partnership Unit [Line Items]
Sale of Stock, Number of Shares Issued in Transaction			226,695
Offering Program
Earnings Per Common Partnership Unit [Line Items]
Common stock, shares authorized (in shares)		16,000,000
Upfront costs		$ 200,000
Dividend Declared
Earnings Per Common Partnership Unit [Line Items]
Dividends payable (in dollars per share)	$ 0.19
Class A Units
Earnings Per Common Partnership Unit [Line Items]
Redeemable limited partnership unit price (in dollars per share)			$ 13.42	$ 11.91	$ 15.75
Limited partners' capital account, units outstanding (in units)			823,983		981,634
BRANDYWINE OPERATING PARTNERSHIP, L.P.
Earnings Per Common Partnership Unit [Line Items]
Preferred units, outstanding (in units)			0	0
Repurchase program, number of mirror unit of operating partnership retired for each common share repurchased			1
Redeemable limited partnership units issued (in units)			823,983	981,634
Redeemable limited partnership units outstanding (in units)			823,983	981,634