Debt - Mortgage Maturities (Details) - Mortgages payable - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Schedule of maturities for outstanding mortgage indebtedness
2018	$ 7,575
2019	0
2020	41,000
2021	12,627
2022	50,982
Thereafter	128,167
Total	$ 240,351	$ 370,804

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
-SubTopic 20
-Section 50
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
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-Paragraph 3
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