Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
OPERATING ACTIVITIES
Net income	$ 27,202	$ 40,132	$ 45,637
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred rent revenue and amortization of lease intangibles	(1,157)	(2,547)	(2,637)
Depreciation and amortization	107,093	83,278	71,319
Amortization of debt issuance costs and debt fair value adjustments	1,530	3,058	4,473
Stock-based compensation expense	3,039	4,735	2,414
Settlement of forward interest rate swap agreement	0	10,667	0
Other noncash interest expense	(1,279)	(1,114)	(231)
Other, net	383	901	(769)
Changes in operating assets and liabilities
Change in accounts receivable	(336)	(1,116)	(2,347)
Change in other assets	(227)	(499)	(982)
Change in accounts payable and accrued expenses	(3,297)	7,632	1,371
Change in security deposits payable	2,274	456	158
Change in other liabilities and deferred credits	1,282	270	2,275
Net cash provided by operating activities	136,507	145,853	120,681
INVESTING ACTIVITIES
Acquisition of real estate, net	0	278,141	0
Capital expenditures	(54,411)	(47,496)	(59,633)
Leasing commissions	(9,936)	(4,927)	(3,572)
Net cash used in investing activities	(64,347)	(330,564)	(63,205)
FINANCING ACTIVITIES
Repayment of secured notes payable	(97,124)	(167,139)	(136,974)
Proceeds from unsecured term loan	0	0	150,000
Proceeds from unsecured line of credit	84,000	173,000	34,000
Repayment of unsecured line of credit	20,000	193,000	44,000
Proceeds from issuance of unsecured notes payable	0	450,000	0
Debt issuance costs	(2,727)	(2,401)	(2,055)
Proceeds from issuance of common stock, net	(236)
Proceeds from issuance of common stock, net		29,873	9,640
Dividends paid to common stock and unitholders	(70,228)	(67,537)	(64,077)
Shares withheld for employee taxes	(527)	(882)	(807)
Net cash provided by (used in) financing activities	(106,842)	221,914	(54,273)
Net (decrease) increase in cash and cash equivalents	(34,682)	37,203	3,203
Cash, cash equivalents and restricted cash, beginning of year	91,954	54,751	51,548
Cash, cash equivalents and restricted cash, end of year	57,272	91,954	54,751
Cash and cash equivalents	47,956	82,610	44,801
Restricted cash	9,316	9,344	9,950
American Assets Trust, L.P.
OPERATING ACTIVITIES
Net income	27,202	40,132	45,637
Adjustments to reconcile net income to net cash provided by operating activities:
Deferred rent revenue and amortization of lease intangibles	(1,157)	(2,547)	(2,637)
Depreciation and amortization	107,093	83,278	71,319
Amortization of debt issuance costs and debt fair value adjustments	1,530	3,058	4,473
Stock-based compensation expense	3,039	4,735	2,414
Settlement of forward interest rate swap agreement	0	10,667	0
Other noncash interest expense	(1,279)	(1,114)	(231)
Other, net	383	901	(769)
Changes in operating assets and liabilities
Change in accounts receivable	(336)	(1,116)	(2,347)
Change in other assets	(227)	(499)	(982)
Change in accounts payable and accrued expenses	(3,297)	7,632	1,371
Change in security deposits payable	2,274	456	158
Change in other liabilities and deferred credits	1,282	270	2,275
Net cash provided by operating activities	136,507	145,853	120,681
INVESTING ACTIVITIES
Acquisition of real estate, net	0	278,141	0
Capital expenditures	(54,411)	(47,496)	(59,633)
Leasing commissions	(9,936)	(4,927)	(3,572)
Net cash used in investing activities	(64,347)	(330,564)	(63,205)
FINANCING ACTIVITIES
Repayment of secured notes payable	(97,124)	(167,139)	(136,974)
Proceeds from unsecured term loan	0	0	150,000
Proceeds from unsecured line of credit	84,000	173,000	34,000
Repayment of unsecured line of credit	20,000	193,000	44,000
Proceeds from issuance of unsecured notes payable	0	450,000	0
Debt issuance costs	(2,727)	(2,401)	(2,055)
Proceeds from issuance of common stock, net	(236)
Contributions from American Assets Trust, Inc.		29,873	9,640
Dividends paid to common stock and unitholders	(70,228)	(67,537)	(64,077)
Shares withheld for employee taxes	(527)	(882)	(807)
Net cash provided by (used in) financing activities	(106,842)	221,914	(54,273)
Net (decrease) increase in cash and cash equivalents	(34,682)	37,203	3,203
Cash, cash equivalents and restricted cash, beginning of year	91,954	54,751	51,548
Cash, cash equivalents and restricted cash, end of year	57,272	91,954	54,751
Cash and cash equivalents	47,956	82,610	44,801
Restricted cash	$ 9,316	$ 9,344	$ 9,950