SIGNIFICANT ACCOUNTING POLICIES SIGNIFICANT ACCOUNTING POLICIES (Details 5) - USD ($)		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Real Estate Properties [Line Items]
Indirect leasing costs		$ 661,000	$ 411,000	$ 0
Operating Lease, Lease Income		271,094,000	248,237,000
Operating Lease, Variable Lease Income	[1]	91,575,000	82,576,000
Income from real estate operations		362,669,000	330,813,000	$ 299,018,000
Operating Leases, Future Minimum Payments Receivable, Current		272,402,000
Operating Leases, Future Minimum Payments Receivable, in Two Years		235,872,000
Operating Leases, Future Minimum Payments Receivable, in Three Years		192,444,000
Operating Leases, Future Minimum Payments Receivable, in Four Years		148,871,000
Operating Leases, Future Minimum Payments Receivable, in Five Years		104,511,000
Operating Leases, Future Minimum Payments Receivable, Thereafter		166,467,000
Operating Leases, Future Minimum Payments Receivable		1,120,567,000
Right of use assets - Office Leases		2,131,000	2,115,000
Operating Lease, Right-of-Use Asset		11,073,000	$ 11,997,000
Income from real estate operations from lease concessions		1,483,000
Amount of executed rent deferral agreements		1,700,000
Qualifying rent deferral agreements, FASB COVID guidance		$ 1,400,000

[1] Primarily includes tenant reimbursements for real estate taxes, insurance and common area maintenance.