Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Total principal	$ 61,537	$ 88,270
Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Total principal	62,179	89,095
Unamortized debt issuance costs	(642)	(825)
Total	61,537	88,270
March 29, 2018 [Member]
Debt Instrument [Line Items]
Total principal	0	25,000
October 2019 [Member]
Debt Instrument [Line Items]
Total principal	21,500	21,500
January 2020 [Member]
Debt Instrument [Line Items]
Total principal	2,345	3,573
February 2020 [Member]
Debt Instrument [Line Items]
Total principal	2,896	2,963
January 1, 2023 [Member]
Debt Instrument [Line Items]
Total principal	23,640	23,640
September 2023 [Member]
Debt Instrument [Line Items]
Total principal	5,003	5,131
July 2026 [Member]
Debt Instrument [Line Items]
Total principal	$ 6,795	$ 7,288

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

+ References

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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