Intangible Assets and Goodwill (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014	Dec. 31, 2012	Dec. 31, 2011
Finite Lived Intangible Assets [Line Items]
Amortization expense, intangible assets	$ 245	$ 260
Goodwill	6,158	6,158
Equity Partners [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill	573	573			$ 600
HGP [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill	2,040	2,040		$ 4,700
NLEX [Member]
Finite Lived Intangible Assets [Line Items]
Goodwill	$ 3,545	$ 3,545	$ 3,500