Consolidated Balance Sheets - USD ($) $ in Thousands		Dec. 31, 2020	Dec. 31, 2019
ASSETS
Operating real estate		$ 3,155,280	$ 3,096,886
Construction in progress		91,047	91,264
Held for development		547	547
Total Real estate, at cost		3,246,874	3,188,697
Accumulated depreciation		(754,140)	(665,222)
Net real estate		2,492,734	2,523,475
Cash and cash equivalents		137,333	99,303
Restricted cash		1,716	10,148
Accounts receivable, net		6,938	12,016
Deferred rent receivables, net		72,476	52,171
Other assets, net		106,112	93,220
TOTAL ASSETS		2,817,309	2,790,333
LIABILITIES AND EQUITY
Secured notes payable		110,923	161,879
Unsecured notes payable, net		1,196,677	1,195,780
Unsecured line of credit, net		99,151	0
Accounts payable and accrued expenses		59,262	62,576
Security deposits payable		6,590	8,316
Other liabilities and deferred credits		91,300	68,110
Total liabilities		1,563,903	1,496,661
Commitments and contingencies (Note 12)
Common stock, shares authorized		490,000,000	490,000,000
Common stock, par value (in dollars per share)		$ 0.01	$ 0.01
Common stock, shares issued		60,476,292	60,068,228
Common stock, shares outstanding		60,476,292	60,068,228
American Assets Trust, Inc. stockholders' equity
Common stock, $0.01 par value, 490,000,000 shares authorized, 60,476,292 and 60,068,228 shares issued and outstanding at December 31, 2020 and December 31, 2019, respectively		$ 605	$ 601
Additional paid-in capital		1,445,644	1,452,014
Accumulated dividends in excess of net income		(176,560)	(144,378)
Accumulated other comprehensive income		1,753	5,680
Total American Assets Trust, Inc. stockholders' equity		1,271,442	1,313,917
Noncontrolling interests		(18,036)	(20,245)
Total equity		1,253,406	1,293,672
TOTAL LIABILITIES AND EQUITY		2,817,309	2,790,333
American Assets Trust, L.P.
ASSETS
Operating real estate		3,155,280	3,096,886
Construction in progress		91,047	91,264
Held for development		547	547
Total Real estate, at cost		3,246,874	3,188,697
Accumulated depreciation		(754,140)	(665,222)
Net real estate		2,492,734	2,523,475
Cash and cash equivalents		137,333	99,303
Restricted cash		1,716	10,148
Accounts receivable, net		6,938	12,016
Deferred rent receivables, net		72,476	52,171
Other assets, net		106,112	93,220
TOTAL ASSETS		2,817,309	2,790,333
LIABILITIES AND EQUITY
Secured notes payable		110,923	161,879
Unsecured notes payable, net		1,196,677	1,195,780
Unsecured line of credit, net		99,151	0
Accounts payable and accrued expenses		59,262	62,576
Security deposits payable		6,590	8,316
Other liabilities and deferred credits		91,300	68,110
Total liabilities		1,563,903	1,496,661
American Assets Trust, Inc. stockholders' equity
Accumulated other comprehensive income		2,737	7,716
TOTAL LIABILITIES AND EQUITY		2,817,309	2,790,333
Partners' Capital [Abstract]
Limited partners' capital, 16,181,537 and 16,390,548 units issued and outstanding as of December 31, 2020 and December 31, 2019, respectively		(19,020)	(22,281)
General partner's capital, 60,476,292 and 60,068,228 units issued and outstanding as of December 31, 2020 and December 31, 2019, respectively		1,269,689	1,308,237
Total capital		1,253,406	1,293,672
Limited Partner | American Assets Trust, L.P.
Partners' Capital [Abstract]
Total capital	[1]	(19,020)	(22,281)
General Partner | American Assets Trust, L.P.
Partners' Capital [Abstract]
Total capital	[2]	1,269,689	1,308,237
Accumulated Other Comprehensive Income (Loss) | American Assets Trust, L.P.
Partners' Capital [Abstract]
Total capital		$ 2,737	$ 7,716

[1] Consists of limited partnership interests held by third parties.

[2] Consists of general and limited partnership interests held by American Assets Trust, Inc.