Indebtedness - Scheduled Principal Repayments and Term-loan Maturities (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Principal repayments and maturities
2021	$ 107,833
2022	99,237
2023	156,380
2024	108,264
2025	286,646
Thereafter	204,452
Total (1)	962,812	$ 960,819
Monthly Principal Amortization
Principal repayments and maturities
2021	10,682
2022	9,667
2023	9,060
2024	9,346
2025	7,539
Thereafter	91,356
Total (1)	137,650
Balloon Payments At Loan Maturity
Principal repayments and maturities
2021	97,151
2022	89,570
2023	147,320
2024	98,918
2025	279,107
Thereafter	113,096
Total (1)	$ 825,162

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
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-SubTopic 20
-Section 50
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