Debt - Aggregate Principal Repayments on Mortgage Notes (Details) - Mortgages [Member] - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
July 1, 2020 - December 31, 2020	$ 78,261
2021	299,015
2022	266,951
2023	124,217
2024	621,021
2025	1,078
Thereafter	5,889
Total	$ 1,396,432	$ 1,529,057

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 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 after 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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