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Basis of Presentation (Details) $ in Thousands	3 Months Ended		6 Months Ended
Basis of Presentation (Details) $ in Thousands	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) segment	Jun. 30, 2017 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of reportable segments \| segment			5
Total expenses	$ 7,419	$ 8,018	$ 19,343	$ 17,282
Other loss, net	(10)	(275)	(24)	(289)
Total revenues	$ 5,070	5,963	$ 18,539	11,665
Accounting Standards Update 2017-07
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Other loss, net		(126)		(320)
Revenue, Sale Of Land \| Accounting Standards Update 2014-09 \| Calculated under Revenue Guidance in Effect before Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		475
Profit		411
Revenue, Sale Of Land \| Accounting Standards Update 2014-09 \| Difference between Revenue Guidance in Effect before and after Topic 606
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Total revenues		$ 73
Profit				$ 9