SECURED FINANCING - Future Mortgage Loan Principal Payments (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Debt Disclosure [Abstract]
2019 (remaining)	$ 804
2020	12,989
2021	3,491
2022	20,034
2023	3,844
Later years	450,273
Total	$ 491,435

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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-Topic 470
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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 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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