For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Leases - Lessor (Details) - USD ($) $ in Thousands	12 Months Ended
Leases - Lessor (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Lessor, Lease, Description [Line Items]
Revenues	$ 224,962	$ 205,814	$ 206,148
Revenue Benchmark \| Bloomberg \| Customer Concentration Risk
Lessor, Lease, Description [Line Items]
Revenues	$ 120,351	$ 115,129	$ 113,140
Percentage rent contributed by tenant	54.00%	56.00%	55.00%
Minimum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, term (years)	5 years
Maximum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, term (years)	25 years
The Alexander apartment tower \| Minimum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, term (years)	1 year
The Alexander apartment tower \| Maximum
Lessor, Lease, Description [Line Items]
Lessor, operating lease, term (years)	2 years