Indebtedness - Scheduled Principal Repayments and Term-loan Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Principal repayments and maturities
2020	$ 10,191
2021	143,038
2022	116,374
2023	132,429
2024	164,960
Thereafter	393,827
Total	960,819	$ 700,722
Monthly Principal Amortization
Principal repayments and maturities
2020	10,191
2021	10,914
2022	9,683
2023	7,752
2024	6,982
Thereafter	72,749
Total	118,271
Balloon Payments At Loan Maturity
Principal repayments and maturities
2020	0
2021	132,124
2022	106,691
2023	124,677
2024	157,978
Thereafter	321,078
Total	$ 842,548

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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