DEBT OBLIGATIONS - Consolidated Debt Obligations Outstanding (Details) - USD ($)	6 Months Ended
Jun. 30, 2022	Dec. 31, 2021
Consolidated debt obligations
Principal balance outstanding	$ 2,042,610,000
Plus: original issue premium (discount), net	(7,212,000)
Less: deferred financing costs	(7,063,000)
Debt, net	2,042,759,000
Unsecured Debt
Consolidated debt obligations
Principal balance outstanding	2,042,610,000	$ 1,851,610,000
Plus: original issue premium (discount), net	7,212,000	8,187,000
Less: deferred financing costs	(7,063,000)	(6,211,000)
Debt, net	2,042,759,000	1,853,586,000
Unsecured Debt \| $600 million Unsecured Credit Facility
Consolidated debt obligations
Debt instrument, face amount	600,000,000
Principal balance outstanding	$ 214,000,000	23,000,000
Unsecured Debt \| $600 million Unsecured Credit Facility \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Consolidated debt obligations
Spread on variable rate	1.15%
Unsecured Debt \| $600 million Unsecured Credit Facility \| Daily SOFR Adjustment
Consolidated debt obligations
Spread on variable rate	0.10%
Unsecured Debt \| Term loan
Consolidated debt obligations
Principal balance outstanding	$ 250,000,000	250,000,000
Spread on variable rate	1.20%
Effective interest rate	2.87%
Unsecured Debt \| Term loan \| Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Consolidated debt obligations
Spread on variable rate	1.20%
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%

Consolidated Debt Obligations Abstract.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Face (par) amount of debt instrument at time of issuance.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Amount, after accumulated amortization, of debt discount (premium).

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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