Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	490,000,000us-gaap_CommonStockSharesAuthorized	490,000,000us-gaap_CommonStockSharesAuthorized
Common stock, shares outstanding	43,701,669us-gaap_CommonStockSharesOutstanding	40,512,563us-gaap_CommonStockSharesOutstanding
American Assets Trust, L.P.
Limited Partners' Capital Account, Units Issued	17,905,257	17,917,109
Limited Partners' Capital Account, Units Outstanding	17,905,257	17,917,109
General Partners' Capital Account, Units Issued	43,701,669	40,512,563
General Partners' Capital Account, Units Outstanding	43,701,669	40,512,563

Face amount or stated value per share of common stock.

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