SECURED AND UNSECURED DEBT, NET - Unsecured Maturities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Aggregate maturities of unsecured debt
2020	$ 327,592
2021	33,560
2022	9,159
2023	695,965
2024	410,924
2025	473,189
2026	351,070
2027	301,111
2028	422,465
2029	444,584
Thereafter	1,399,500
Subtotal	4,869,119
Non-cash (a)	16,019
Long-term Debt, Total	4,885,138	$ 4,707,524
Secured Debt
Aggregate maturities of unsecured debt
2020	112,592
2021	8,763
2022	9,159
2023	295,965
2024	95,280
2025	173,189
2026	51,070
2027	1,111
2028	122,465
2029	144,584
Thereafter	99,500
Subtotal	1,113,678
Non-cash (a)	30,523
Long-term Debt, Total	1,144,201
Unsecured Debt
Aggregate maturities of unsecured debt
2020	215,000
2021	24,797
2023	400,000
2024	315,644
2025	300,000
2026	300,000
2027	300,000
2028	300,000
2029	300,000
Thereafter	1,300,000
Subtotal	3,755,441
Non-cash (a)	(14,504)
Long-term Debt, Total	3,740,937
Fixed Rate Debt \| Secured Debt
Aggregate maturities of unsecured debt
2020	112,592
2021	8,763
2022	9,159
2023	295,965
2024	95,280
2025	173,189
2026	51,070
2027	1,111
2028	122,465
2029	144,584
Thereafter	72,500
Subtotal	1,086,678
Non-cash (a)	30,585
Long-term Debt, Total	1,117,263
Variable Rate Debt \| Secured Debt
Aggregate maturities of unsecured debt
Thereafter	27,000
Subtotal	27,000
Non-cash (a)	(62)
Long-term Debt, Total	$ 26,938

Amount, after accumulated amortization, of fair value adjustment, debt discount (premium) and deferred financing cost.

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Long-term debt, maturities, repayment of principle in year eight.

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Long-term debt, maturities, repayment of principle in year nine.

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Long-term debt, maturities, repayment of principle in year seven.

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Long-term debt, maturities, repayment of principle in year six.

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Long-term debt, maturities, repayment of principle in year ten.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the tenth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Maturities of unsecured debt.

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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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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing in the remainder of the fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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