Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	490,000,000	490,000,000
Common stock, shares outstanding	45,732,109	45,407,719
American Assets Trust, L.P.
Limited Partners' Capital Account, Units Issued	17,888,822	17,899,516
Limited Partners' Capital Account, Units Outstanding	17,888,822	17,899,516
General Partners' Capital Account, Units Issued	45,732,109	45,407,719
General Partners' Capital Account, Units Outstanding	45,732,109	45,407,719
Common Stock
Common stock, shares issued	45,732,109	45,407,719