Consolidated Statement of Partners' Capital (Unaudited) - LP - USD ($) $ in Thousands		Total	Interest Expense	Early Extinguishment of Debt	American Assets Trust, L.P.	American Assets Trust, L.P. Interest Expense	American Assets Trust, L.P. Early Extinguishment of Debt	American Assets Trust, L.P. Accumulated Other Comprehensive Income (Loss)	American Assets Trust, L.P. Accumulated Other Comprehensive Income (Loss) Interest Expense	American Assets Trust, L.P. Accumulated Other Comprehensive Income (Loss) Early Extinguishment of Debt	American Assets Trust, L.P. Limited Partner		American Assets Trust, L.P. General Partner
Beginning partners' capital account (shares) at Dec. 31, 2020											16,181,537	[1]	60,476,292	[2]
Beginning partners' capital account at Dec. 31, 2020					$ 1,253,406			$ 2,737			$ (19,020)	[1]	$ 1,269,689	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		$ 1,733			1,733						339	[1]	$ 1,394	[2]
Forfeiture of restricted units (shares)	[2]												(4,006)
Distributions					(21,463)						$ (4,531)	[1]	$ (16,932)	[2]
Stock-based compensation					1,484								$ 1,484	[2]
Other comprehensive income - change in value of interest rate swaps		747			747			747
Reclassification of amortization of forward-starting swap realized gain			$ (275)	$ (193)		$ (275)	$ (193)		$ (275)	$ (193)
Ending partners' capital account (shares) at Mar. 31, 2021											16,181,537	[1]	60,472,286	[2]
Ending partners' capital account at Mar. 31, 2021					1,235,439			3,016			$ (23,212)	[1]	$ 1,255,635	[2]
Beginning partners' capital account (shares) at Dec. 31, 2020											16,181,537	[1]	60,476,292	[2]
Beginning partners' capital account at Dec. 31, 2020					1,253,406			2,737			$ (19,020)	[1]	$ 1,269,689	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		13,220			13,220
Other comprehensive income - change in value of interest rate swaps		1,222			1,222
Reclassification of amortization of forward-starting swap realized gain			(550)	(193)		(550)	(193)
Ending partners' capital account (shares) at Jun. 30, 2021											16,181,537	[1]	60,474,866	[2]
Ending partners' capital account at Jun. 30, 2021					1,227,146			3,216			$ (25,332)	[1]	$ 1,249,262	[2]
Beginning partners' capital account (shares) at Mar. 31, 2021											16,181,537	[1]	60,472,286	[2]
Beginning partners' capital account at Mar. 31, 2021					1,235,439			3,016			$ (23,212)	[1]	$ 1,255,635	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		11,487			11,487						2,411	[1]	$ 9,076	[2]
Issuance of restricted stock (shares)	[2]												5,184
Forfeiture of restricted units (shares)	[2]												(2,604)
Distributions					(21,464)						$ (4,531)	[1]	$ (16,933)	[2]
Stock-based compensation					1,484								$ 1,484	[2]
Other comprehensive income - change in value of interest rate swaps		475			475			475
Reclassification of amortization of forward-starting swap realized gain		(275)	(275)	0		(275)	0		(275)
Ending partners' capital account (shares) at Jun. 30, 2021											16,181,537	[1]	60,474,866	[2]
Ending partners' capital account at Jun. 30, 2021					1,227,146			3,216			$ (25,332)	[1]	$ 1,249,262	[2]
Beginning partners' capital account (shares) at Dec. 31, 2021											16,181,537	[1]	60,525,580	[2]
Beginning partners' capital account at Dec. 31, 2021					1,210,123			4,169			$ (30,138)	[1]	$ 1,236,092	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		13,514			13,514						2,836	[1]	$ 10,678	[2]
Forfeiture of restricted units (shares)	[2]												(3,121)
Distributions					(24,545)						$ (5,178)	[1]	$ (19,367)	[2]
Stock-based compensation					1,489								$ 1,489	[2]
Shares withheld for employee taxes (shares)	[2]												(416)
Shares withheld for employee taxes		(15)			(15)								$ (15)	[2]
Other comprehensive income - change in value of interest rate swaps		5,596			5,596			5,596
Reclassification of amortization of forward-starting swap realized gain			(275)			(275)			(275)
Ending partners' capital account (shares) at Mar. 31, 2022											16,181,537	[1]	60,522,043	[2]
Ending partners' capital account at Mar. 31, 2022					1,205,887			9,490			$ (32,480)	[1]	$ 1,228,877	[2]
Beginning partners' capital account (shares) at Dec. 31, 2021											16,181,537	[1]	60,525,580	[2]
Beginning partners' capital account at Dec. 31, 2021					1,210,123			4,169			$ (30,138)	[1]	$ 1,236,092	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		27,102			27,102
Other comprehensive income - change in value of interest rate swaps		8,910			8,910
Reclassification of amortization of forward-starting swap realized gain			(550)	0		(550)	0
Ending partners' capital account (shares) at Jun. 30, 2022											16,181,537		60,528,115
Ending partners' capital account at Jun. 30, 2022					1,199,968			12,529			$ (34,806)		$ 1,222,245
Beginning partners' capital account (shares) at Mar. 31, 2022											16,181,537	[1]	60,522,043	[2]
Beginning partners' capital account at Mar. 31, 2022					1,205,887			9,490			$ (32,480)	[1]	$ 1,228,877	[2]
Increase (Decrease) in Partners' Capital [Roll Forward]
Net income		13,588			13,588						2,852		$ 10,736
Issuance of restricted stock (shares)													6,072
Distributions					(24,547)						$ (5,178)		$ (19,369)
Stock-based compensation					2,001								$ 2,001
Other comprehensive income - change in value of interest rate swaps		$ 3,314			3,314			3,314
Reclassification of amortization of forward-starting swap realized gain			$ (275)	$ 0		$ (275)	$ 0		$ (275)
Ending partners' capital account (shares) at Jun. 30, 2022											16,181,537		60,528,115
Ending partners' capital account at Jun. 30, 2022					$ 1,199,968			$ 12,529			$ (34,806)		$ 1,222,245

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

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