SECURED AND UNSECURED DEBT, NET - Unsecured Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Aggregate maturities of unsecured debt
2020	$ 230,655
2021	2,680
2022	24,874
2023	415,038
2024	294,030
2025	473,189
2026	351,070
2027	301,111
2028	422,466
2029	444,584
Thereafter	1,960,430
Subtotal	4,920,127
Non-cash (a)	(2,481)
Long-term Debt, Total	4,917,646	$ 4,707,524
Secured Debt
Aggregate maturities of unsecured debt
2020	655
2021	2,680
2022	2,788
2023	65,038
2024	95,280
2025	173,189
2026	51,070
2027	1,111
2028	122,466
2029	144,584
Thereafter	260,430
Subtotal	919,291
Non-cash (a)	13,796
Long-term Debt, Total	933,087
Unsecured Debt
Aggregate maturities of unsecured debt
2020	230,000
2021	0
2022	22,086
2023	350,000
2024	198,750
2025	300,000
2026	300,000
2027	300,000
2028	300,000
2029	300,000
Thereafter	1,700,000
Subtotal	4,000,836
Non-cash (a)	(16,277)
Long-term Debt, Total	3,984,559
Fixed Rate Debt \| Secured Debt
Aggregate maturities of unsecured debt
2020	655
2021	2,680
2022	2,788
2023	65,038
2024	95,280
2025	173,189
2026	51,070
2027	1,111
2028	122,466
2029	144,584
Thereafter	233,430
Subtotal	892,291
Non-cash (a)	13,866
Long-term Debt, Total	906,157
Variable Rate Debt \| Secured Debt
Aggregate maturities of unsecured debt
Thereafter	27,000
Subtotal	27,000
Non-cash (a)	(70)
Long-term Debt, Total	$ 26,930

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 repayments of principal after year nine.

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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 requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in remainder of current fiscal year.

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