Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
ASSETS
Operating real estate	$ 2,167,426	$ 2,163,444
Construction in progress	86,189	73,121
Held for development	9,461	9,463
Total Real estate, at cost	2,263,076	2,246,028
Accumulated depreciation	(426,076)	(411,166)
Net real estate	1,837,000	1,834,862
Cash and cash equivalents	44,007	39,925
Restricted cash	9,295	11,623
Accounts receivable, net	7,586	7,518
Deferred rent receivables, net	38,633	38,422
Other assets, net	41,305	41,939
TOTAL ASSETS	1,977,826	1,974,289
LIABILITIES AND EQUITY
Secured notes payable, net	494,883	579,000
Unsecured notes payable, net	545,883	446,613
Unsecured line of credit	20,000	30,000
Accounts payable and accrued expenses	37,014	31,821
Security deposits payable	6,065	5,956
Other liabilities and deferred credits, net	53,580	51,972
Total liabilities	$ 1,157,425	$ 1,145,362
Commitments and contingencies (Note 11)
American Assets Trust, Inc. stockholders’ equity
Common stock, $0.01 par value, 490,000,000 shares authorized, 45,407,402 and 45,407,719 shares issued and outstanding at March 31, 2016 and December 31, 2015, respectively	$ 454	$ 454
Additional paid-in capital	864,038	863,432
Accumulated dividends in excess of net income	(67,724)	(64,066)
Accumulated other comprehensive loss	(3,143)	(258)
Total American Assets Trust, Inc. stockholders’ equity	793,625	799,562
Noncontrolling interests	26,776	29,365
Total equity	820,401	828,927
Partners' Capital [Abstract]
TOTAL LIABILITIES AND EQUITY	1,977,826	1,974,289
American Assets Trust, L.P.
ASSETS
Operating real estate	2,167,426	2,163,444
Construction in progress	86,189	73,121
Held for development	9,461	9,463
Total Real estate, at cost	2,263,076	2,246,028
Accumulated depreciation	(426,076)	(411,166)
Net real estate	1,837,000	1,834,862
Cash and cash equivalents	44,007	39,925
Restricted cash	9,295	11,623
Accounts receivable, net	7,586	7,518
Deferred rent receivables, net	38,633	38,422
Other assets, net	41,305	41,939
TOTAL ASSETS	1,977,826	1,974,289
LIABILITIES AND EQUITY
Secured notes payable, net	494,883	579,000
Unsecured notes payable, net	545,883	446,613
Unsecured line of credit	20,000	30,000
Accounts payable and accrued expenses	37,014	31,821
Security deposits payable	6,065	5,956
Other liabilities and deferred credits, net	53,580	51,972
Total liabilities	$ 1,157,425	$ 1,145,362
Commitments and contingencies (Note 11)
American Assets Trust, Inc. stockholders’ equity
Accumulated other comprehensive loss	$ (4,365)	$ (339)
Partners' Capital [Abstract]
Limited partners' capital, 17,899,516 and 17,899,516 units issued and outstanding as of March 31, 2016 and December 31, 2015, respectively	27,998	29,446
General partner's capital, 45,407,402 and 45,407,719 units issued and outstanding as of March 31, 2016 and December 31, 2015, respectively	796,768	799,820
Total capital	820,401	828,927
TOTAL LIABILITIES AND EQUITY	$ 1,977,826	$ 1,974,289