Mortgages Payable - Maturities (Details) - Mortgages payable - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Maturity of mortgages payable, excluding net premiums
2021	$ 44,200
2022	111,800
2023	20,600
2024	112,200
2025	700
Thereafter	10,100
Totals	$ 299,631	$ 408,419

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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-Section 50
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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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-Publisher FASB
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-SubTopic 10
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