Amount recovered for reimbursements of operating expense for related party.

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Percentage of investment in related party.

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Term of lessor's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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Expenses recognized resulting from transactions (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of new stock issued during the period.

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Related Party Transactions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Jun. 01, 2021	Jan. 01, 2021	Mar. 01, 2019
Related Party Transaction [Line Items]
Total rental income		$ 330,312	$ 343,865	$ 309,537
Investment in WBW CHP LLC, in percentage		47.70%
WBW CHP LLC
Related Party Transaction [Line Items]
Recovered reimbursements of operating expenses of WBW CHP LLC		$ 1,000	$ 1,100	1,100
Common Stock
Related Party Transaction [Line Items]
Common shares issued (in shares)			11,871,552
Insurance Company of the West, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Total rental income		0	$ 0	100
American Assets, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Total rental income		200	200	100
Lessor, Operating Lease, Term of Contract							3 years
Operating Lease, Lease Income		200
American Assets, Inc. \| Board of Directors Chairman \| Forecast
Related Party Transaction [Line Items]
Lessor, Operating Lease, Term of Contract						10 years
Operating Lease, Lease Income	$ 200
EDisability, LLC \| Board of Directors Chairman
Related Party Transaction [Line Items]
Total rental income		200	200	100
EDisability, LLC \| Board of Directors Chairman \| Forecast
Related Party Transaction [Line Items]
Lessor, Operating Lease, Term of Contract					3 years
Operating Lease, Lease Income	$ 100
AAI Aviation, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Aviation expense		$ 0	$ 200	$ 100
Insurance Company of the West, Inc. \| Board of Directors Chairman
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling		33.00%
Insurance Company of the West, Inc. \| Common Stock \| Board of Directors Chairman
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling		13.40%
Insurance Company of the West, Inc. \| Member Units \| Board of Directors Chairman
Related Party Transaction [Line Items]
Percentage of ownership interests classified as noncontrolling		19.50%