Mortgages Payable - Summary of Maturities (Details) - Mortgages Payable - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Debt
Unamortized net premiums	$ 3,300
Deferred financing costs	143	$ 183
Maturity of mortgages payable, excluding net premiums
2019	1,200
2020	82,400
2021	67,000
2022	109,700
2023	6,700
Thereafter	11,900
Totals	$ 278,882	$ 298,377

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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