Debt (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Mortgages Notes Payable	$ 69,067	$ 100,391
Unamortized Debt Issuance Expense	(3,100)	(2,600)
Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	70,007	101,584
Unamortized Debt Issuance Expense	(940)	(1,193)
Total principal	69,067	100,391
March 11 2016 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	0	8,580
August 19 2016 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	0	20,741
April 4 2018 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	25,000	25,000
January 2020 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	5,114	6,553
February 2020 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	3,049	3,129
January 1 2023 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	23,640	23,640
September 2023 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	5,294	5,448
July 2026 [Member] \| Mortgage Notes Payable [Member]
Debt Instrument [Line Items]
Mortgages Notes Payable	$ 7,910	$ 8,493

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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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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.

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