DEBT OBLIGATIONS - Consolidated Debt Obligations Outstanding (Details)	3 Months Ended
Mar. 31, 2022 USD ($) property	Dec. 31, 2021 USD ($)
Consolidated debt obligations
Principal balance outstanding	$ 1,984,610,000
Plus: original issue premium (discount), net	(7,699,000)
Less: deferred financing costs	(5,726,000)
Debt, net	1,986,583,000
Unsecured Debt
Consolidated debt obligations
Principal balance outstanding	1,984,610,000	$ 1,851,610,000
Plus: original issue premium (discount), net	7,699,000	8,187,000
Less: deferred financing costs	(5,726,000)	(6,211,000)
Debt, net	1,986,583,000	1,853,586,000
Unsecured Debt \| $600 million Unsecured Credit Facility
Consolidated debt obligations
Debt instrument, face amount	600,000,000
Principal balance outstanding	$ 156,000,000	23,000,000
Number of extensions \| property	2
Extension term	6 months
Debt extension fees for first six months, percentage	0.0625%
Debt extension fees for next six months, percentage	0.075%
Unsecured Debt \| $600 million Unsecured Credit Facility \| LIBOR
Consolidated debt obligations
Spread on variable rate	1.10%
Unsecured Debt \| Term Loan - Swapped to fixed
Consolidated debt obligations
Principal balance outstanding	$ 250,000,000	250,000,000
Effective interest rate	2.87%
Unsecured Debt \| $350.0M 3.95% Guaranteed Notes due 2023
Consolidated debt obligations
Debt instrument, face amount	$ 350,000,000.0
Debt instrument, interest rate, stated percentage	3.95%
Principal balance outstanding	$ 350,000,000	350,000,000
Effective interest rate	3.87%
Unsecured Debt \| $350.0M 4.10% Guaranteed Notes due 2024
Consolidated debt obligations
Debt instrument, face amount	$ 350,000,000.0
Debt instrument, interest rate, stated percentage	4.10%
Principal balance outstanding	$ 350,000,000	350,000,000
Effective interest rate	3.78%
Unsecured Debt \| $450.0M 3.95% Guaranteed Notes due 2027
Consolidated debt obligations
Debt instrument, face amount	$ 450,000,000.0
Debt instrument, interest rate, stated percentage	3.95%
Principal balance outstanding	$ 450,000,000	450,000,000
Effective interest rate	4.03%
Unsecured Debt \| $350.0M 4.55% Guaranteed Notes due 2029
Consolidated debt obligations
Debt instrument, face amount	$ 350,000,000.0
Debt instrument, interest rate, stated percentage	4.55%
Principal balance outstanding	$ 350,000,000	350,000,000
Effective interest rate	4.30%
Unsecured Debt \| Indenture IA (Preferred Trust I)
Consolidated debt obligations
Principal balance outstanding	$ 27,062,000	27,062,000
Unsecured Debt \| Indenture IA (Preferred Trust I) \| LIBOR
Consolidated debt obligations
Spread on variable rate	1.25%
Unsecured Debt \| Indenture IB (Preferred Trust I)
Consolidated debt obligations
Principal balance outstanding	$ 25,774,000	25,774,000
Unsecured Debt \| Indenture IB (Preferred Trust I) \| LIBOR
Consolidated debt obligations
Spread on variable rate	1.25%
Unsecured Debt \| Indenture II (Preferred Trust II)
Consolidated debt obligations
Principal balance outstanding	$ 25,774,000	$ 25,774,000
Unsecured Debt \| Indenture II (Preferred Trust II) \| LIBOR
Consolidated debt obligations
Spread on variable rate	1.25%

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