UNSECURED BANK CREDIT FACILITIES (Details)	12 Months Ended
	Dec. 31, 2023 USD ($) basisPoints Integer	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Line of Credit Facility [Line Items]
Unsecured bank credit facilities - variable rate, carrying amount	$ (1,520,000)	$ 168,454,000
Unamortized debt issuance costs	(1,520,000)	(1,546,000)
Line of Credit Facility, Maximum Borrowing Capacity	$ 675,000,000	$ 475,000,000
Weighted average interest rates (in hundredths)	5.68%	2.32%	1.01%
Average bank borrowings	$ 0	$ 170,000,000
Amortization of facility fees	1,005,000	713,000	$ 751,000
Amortization of Debt Issuance Costs	1,943,000	1,357,000	1,296,000
Average bank borrowings	49,384,000	182,478,000	95,629,000
Working Cash Line of Credit
Line of Credit Facility [Line Items]
Unsecured bank credit facilities - variable rate, carrying amount	0
Line of Credit Facility, Maximum Borrowing Capacity	$ 50,000,000	50,000,000
Line of Credit Facility, Expiration Date	Jul. 30, 2025
Credit facility, extension option	two six-month extensions
Line of Credit Facility, Interest Rate at Period End	6.255%
Debt Instrument, Covenant Description	Although the Company’s current credit rating is Baa2, given the strength of the Company’s key credit metrics, initial pricing for the credit facilities is based on the BBB+/Baa1 credit ratings level. This favorable pricing level will be retained provided that the Company’s consolidated leverage ratio, as defined in the applicable agreements, remains less than 32.5%
Amortization of Debt Issuance Costs	$ 1,003,000	650,000	$ 606,000
Debt Instrument, Covenant Compliance	The Company’s unsecured bank credit facilities have certain restrictive covenants, such as maintaining minimum debt service coverage and leverage ratios and maintaining insurance coverage, and the Company was in compliance with all of its financial debt covenants at December 31, 2023
Basis spread | basisPoints	77.5
Line of credit, facility fee (in basis points) | basisPoints	15
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 625,000,000	$ 425,000,000
Increase in maximum borrowing capacity	$ 200,000,000
Banks included in the unsecured revolving credit facility group | Integer	11
Credit facility, extension option	two six-month extensions
Line of Credit Facility, Interest Rate at Period End	6.13%
Letters of Credit Outstanding, Amount	$ 2,655,000
Debt Instrument, Maturity Date	Jul. 30, 2025
Line of credit facility, accordion	$ 125,000,000
Sustainability-linked pricing component, interest margin reduction (in basis points)	1
Basis spread | basisPoints	76.5
Line of credit, facility fee (in basis points) | basisPoints	15