Consolidated Statements of Cash Flows (Unaudited)	3 Months Ended	9 Months Ended
	Sep. 30, 2020 USD ($) shares	Sep. 30, 2020 USD ($) shares	Sep. 30, 2019 USD ($)
OPERATING ACTIVITIES
Net income	$ 6,490,000	$ 31,800,000	$ 43,703,000
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred rent revenue and amortization of lease intangibles		(20,025,000)	(3,652,000)
Depreciation and amortization		80,869,000	69,733,000
Amortization of debt issuance costs and debt fair value adjustments		1,109,000	1,096,000
Provision for uncollectable rental income		10,803,000	933,000
Gain on sale of real estate	0	0	(633,000)
Stock-based compensation expense		3,753,000	3,359,000
Settlement of derivative instruments		0	513,000
Lease termination income		0	(4,518,000)
Unrealized loss on hedging activities		551,000	0
Other noncash interest expense		(997,000)	(972,000)
Other, net		(3,208,000)	795,000
Changes in operating assets and liabilities
Change in accounts receivable		(7,502,000)	732,000
Change in other assets		1,453,000	(22,000)
Change in accounts payable and accrued expenses		13,787,000	16,461,000
Change in security deposits payable		(1,787,000)	(1,433,000)
Change in other liabilities and deferred credits		(1,457,000)	(3,983,000)
Net cash provided by operating activities		109,149,000	122,112,000
INVESTING ACTIVITIES
Acquisition of real estate		0	(507,780,000)
Capital expenditures		(48,690,000)	(65,549,000)
Proceeds from sale of real estate, net of selling costs		0	8,191,000
Leasing commissions		(4,884,000)	(8,892,000)
Net cash used in investing activities		(53,574,000)	(574,030,000)
FINANCING ACTIVITIES
Repayment of secured notes payable		(51,003,000)	(20,468,000)
Proceeds from unsecured line of credit		100,000,000	59,000,000
Repayment of unsecured line of credit		0	(123,000,000)
Proceeds from unsecured notes payable		0	150,000,000
Debt issuance costs		0	(1,091,000)
Proceeds from issuance of common stock, net		(119,000)	513,934,000
Dividends paid to common stock and unitholders		(57,346,000)	(57,667,000)
Net cash (used in) provided by financing activities		(8,468,000)	520,708,000
Net increase (decrease) in cash and cash equivalents		47,107,000	68,790,000
Cash, cash equivalents and restricted cash, beginning of period		109,451,000	57,272,000
Cash, cash equivalents and restricted cash, end of period	156,558,000	156,558,000	126,062,000
Cash and cash equivalents	155,327,000	155,327,000	115,568,000
Restricted cash	$ 1,231,000	1,231,000	10,494,000
Common Shares
FINANCING ACTIVITIES
Conversion of operating partnership units (in shares) | shares	209,011
Conversion of operating partnership units	$ 2,000
Additional Paid-in Capital
FINANCING ACTIVITIES
Conversion of operating partnership units	(12,003,000)
Accumulated Other Comprehensive Income (Loss)
FINANCING ACTIVITIES
Conversion of operating partnership units	3,000
Noncontrolling Interests - Unitholders in the Operating Partnership
OPERATING ACTIVITIES
Net income	1,365,000
FINANCING ACTIVITIES
Conversion of operating partnership units	11,998,000
American Assets Trust, L.P.
OPERATING ACTIVITIES
Net income	6,490,000	31,800,000	43,703,000
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred rent revenue and amortization of lease intangibles		(20,025,000)	(3,652,000)
Depreciation and amortization		80,869,000	69,733,000
Amortization of debt issuance costs and debt fair value adjustments		1,109,000	1,096,000
Provision for uncollectable rental income		10,803,000	933,000
Gain on sale of real estate	0	0	(633,000)
Stock-based compensation expense		3,753,000	3,359,000
Settlement of derivative instruments		0	513,000
Lease termination income		0	(4,518,000)
Unrealized loss on hedging activities		551,000	0
Other noncash interest expense		(997,000)	(972,000)
Other, net		(3,208,000)	795,000
Changes in operating assets and liabilities
Change in accounts receivable		(7,502,000)	732,000
Change in other assets		1,453,000	(22,000)
Change in accounts payable and accrued expenses		13,787,000	16,461,000
Change in security deposits payable		(1,787,000)	(1,433,000)
Change in other liabilities and deferred credits		(1,457,000)	(3,983,000)
Net cash provided by operating activities		109,149,000	122,112,000
INVESTING ACTIVITIES
Acquisition of real estate		0	(507,780,000)
Capital expenditures		(48,690,000)	(65,549,000)
Proceeds from sale of real estate, net of selling costs		0	8,191,000
Leasing commissions		(4,884,000)	(8,892,000)
Net cash used in investing activities		(53,574,000)	(574,030,000)
FINANCING ACTIVITIES
Repayment of secured notes payable		(51,003,000)	(20,468,000)
Proceeds from unsecured line of credit		100,000,000	59,000,000
Repayment of unsecured line of credit		0	(123,000,000)
Proceeds from unsecured notes payable		0	150,000,000
Debt issuance costs		0	(1,091,000)
Contributions from American Assets Trust, Inc.		(119,000)
Contributions from American Assets Trust, Inc.			513,934,000
Dividends paid to common stock and unitholders		(57,346,000)	(57,667,000)
Net cash (used in) provided by financing activities		(8,468,000)	520,708,000
Net increase (decrease) in cash and cash equivalents		47,107,000	68,790,000
Cash, cash equivalents and restricted cash, beginning of period		109,451,000	57,272,000
Cash, cash equivalents and restricted cash, end of period	156,558,000	156,558,000	126,062,000
Cash and cash equivalents	155,327,000	155,327,000	115,568,000
Restricted cash	1,231,000	$ 1,231,000	$ 10,494,000
American Assets Trust, L.P. | Limited Partner
OPERATING ACTIVITIES
Net income	1,365,000
American Assets Trust, L.P. | General Partner
OPERATING ACTIVITIES
Net income	$ 5,125,000
Conversion of operating partnership units (shares) | shares	209,011
Conversion of operating partnership units	$ (12,001,000)
American Assets Trust, L.P. | Common Shares
FINANCING ACTIVITIES
Conversion of operating partnership units (in shares) | shares		209,011
American Assets Trust, L.P. | Common Shares | Limited Partner
OPERATING ACTIVITIES
Conversion of operating partnership units (shares) | shares	(209,011)
Conversion of operating partnership units	$ 12,001,000