Intangible Assets (Schedule of Company's Intangible Assets) (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Unamortized intangible assets:
Goodwill, Gross Carrying Amount	[1]	$ 12,796	$ 12,796
Goodwill, Accumulated Amortization	[1]	(227)	(227)
Total intangible assets		18,222	18,222
Accumulated Amortization		(4,207)	(4,099)
Customer Lists [Member]
Assets eligible for amortization:
Gross Carrying Amount		4,288	4,288
Accumulated Amortization		(3,163)	(3,071)
Patents [Member]
Assets eligible for amortization:
Gross Carrying Amount		72	72
Accumulated Amortization		(17)	(16)
Non-compete Agreements [Member]
Assets eligible for amortization:
Gross Carrying Amount		332	332
Accumulated Amortization		(332)	(326)
Software [Member]
Assets eligible for amortization:
Gross Carrying Amount		234	234
Accumulated Amortization		(234)	(234)
Other [Member]
Assets eligible for amortization:
Gross Carrying Amount		500	500
Accumulated Amortization		$ (234)	$ (225)

[1] Amortization through December 31, 2001 prior to adoption of FASB ASC 350.