Mortgages and Notes Payable - Maturities of Long-term Debt (Details) - Mortgages, Notes Payable, Credit Facility Borrowings, and Term Loans $ in Thousands	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
2020	$ 71,099
2021	36,597
2022	18,564
2023	20,136
2024	13,856
Thereafter	533,620
Long-term debt, gross	693,872
Unamortized debt issuance costs	(6,161)
Long-term debt	$ 687,711

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, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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