SIGNIFICANT ACCOUNTING POLICIES (Details 3) - USD ($)		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Amortization of debt issuance costs		$ 1,296,000	$ 1,418,000	$ 1,344,000
Amortization of facility fees		751,000	790,000	790,000
Leasing costs amortization expense		16,209,000	14,449,000	13,167,000
Rental Income (Increase) Decrease For Amortization Of Acquired In Place Lease Intangibles		(1,048,000)	(1,451,000)	(1,229,000)
Amortization of Intangible Assets		5,980,000	5,620,000	$ 4,967,000
Future Amortization In Place Lease Expense Year One		6,461,000
Future Amortization In Place Lease Expense Year Two		4,400,000
Future Amortization In Place Lease Expense Year Three		3,276,000
Future Amortization In Place Lease Expense Year Four		2,465,000
Future Amortization In Place Lease Expense Year Five		1,391,000
Real Estate Properties [Line Items]
Land		544,505,000	502,739,000
Tenant and other mprovements		570,627,000	524,954,000
Right of use assets - Ground leases (operating)	[1]	22,635,000	11,073,000
Real Estate Investment Property, at Cost		4,051,325,000	3,519,085,000
In-place lease intangibles		$ 31,561,000	$ 28,107,000
2021 acquisitions
Real Estate Properties [Line Items]
Operating Lease, Weighted Average Remaining Lease Term		2 years 10 months 24 days
2021 acquisitions | Land [Member]
Real Estate Properties [Line Items]
Land		$ 42,554,000
2021 acquisitions | Building and Building Improvements
Real Estate Properties [Line Items]
Buildings and improvements		225,645,000
2021 acquisitions | Tenant and other improvements
Real Estate Properties [Line Items]
Tenant and other mprovements		4,907,000
2021 acquisitions | Right of use assets - ground leases (operating)
Real Estate Properties [Line Items]
Right of use assets - Ground leases (operating)		12,708,000
2021 acquisitions | Total assets acquired
Real Estate Properties [Line Items]
Real Estate Investment Property, at Cost		285,814,000
2021 acquisitions | In-place lease intangibles
Real Estate Properties [Line Items]
In-place lease intangibles		9,949,000
2021 acquisitions | Above market lease intangibles
Real Estate Properties [Line Items]
Above market lease intangibles		6,000
2021 acquisitions | Below market lease intangibles
Real Estate Properties [Line Items]
Below market lease intangibles		(3,836,000)
2021 acquisitions | Operating lease liabilities - ground leases
Real Estate Properties [Line Items]
Operating lease liabilities - Ground leases		(12,708,000)
2021 acquisitions | Total assets acquired, net of liabilities assumed
Real Estate Properties [Line Items]
Total assets acquired, net of liabilities assumed		$ 279,225,000
2020 Acquisitions [Member]
Real Estate Properties [Line Items]
Operating Lease, Weighted Average Remaining Lease Term			3 years 10 months 24 days
2020 Acquisitions [Member] | Land [Member]
Real Estate Properties [Line Items]
Land			$ 23,565,000
2020 Acquisitions [Member] | Building and Building Improvements
Real Estate Properties [Line Items]
Buildings and improvements			42,024,000
2020 Acquisitions [Member] | Tenant and other improvements
Real Estate Properties [Line Items]
Tenant and other mprovements			7,971,000
2020 Acquisitions [Member] | Right of use assets - ground leases (operating)
Real Estate Properties [Line Items]
Right of use assets - Ground leases (operating)			0
2020 Acquisitions [Member] | Total assets acquired
Real Estate Properties [Line Items]
Real Estate Investment Property, at Cost			73,560,000
2020 Acquisitions [Member] | In-place lease intangibles
Real Estate Properties [Line Items]
In-place lease intangibles			3,257,000
2020 Acquisitions [Member] | Above market lease intangibles
Real Estate Properties [Line Items]
Above market lease intangibles			104,000
2020 Acquisitions [Member] | Below market lease intangibles
Real Estate Properties [Line Items]
Below market lease intangibles			(403,000)
2020 Acquisitions [Member] | Operating lease liabilities - ground leases
Real Estate Properties [Line Items]
Operating lease liabilities - Ground leases			0
2020 Acquisitions [Member] | Total assets acquired, net of liabilities assumed
Real Estate Properties [Line Items]
Total assets acquired, net of liabilities assumed			$ 76,518,000
2019 Acquisitions [Member]
Real Estate Properties [Line Items]
Operating Lease, Weighted Average Remaining Lease Term				6 years
2019 Acquisitions [Member] | Land [Member]
Real Estate Properties [Line Items]
Land				$ 76,039,000
2019 Acquisitions [Member] | Building and Building Improvements
Real Estate Properties [Line Items]
Buildings and improvements				144,301,000
2019 Acquisitions [Member] | Tenant and other improvements
Real Estate Properties [Line Items]
Tenant and other mprovements				6,490,000
2019 Acquisitions [Member] | Right of use assets - ground leases (operating)
Real Estate Properties [Line Items]
Right of use assets - Ground leases (operating)				2,679,000
2019 Acquisitions [Member] | Total assets acquired
Real Estate Properties [Line Items]
Real Estate Investment Property, at Cost				229,509,000
2019 Acquisitions [Member] | In-place lease intangibles
Real Estate Properties [Line Items]
In-place lease intangibles				10,020,000
2019 Acquisitions [Member] | Above market lease intangibles
Real Estate Properties [Line Items]
Above market lease intangibles				344,000
2019 Acquisitions [Member] | Below market lease intangibles
Real Estate Properties [Line Items]
Below market lease intangibles				(2,685,000)
2019 Acquisitions [Member] | Operating lease liabilities - ground leases
Real Estate Properties [Line Items]
Operating lease liabilities - Ground leases				(2,679,000)
2019 Acquisitions [Member] | Total assets acquired, net of liabilities assumed
Real Estate Properties [Line Items]
Total assets acquired, net of liabilities assumed				$ 234,509,000

[1] See Ground Leases discussion below for information regarding the Company’s right of use assets for ground leases.