Intangible Assets (Intangible Assets) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,909	$ 5,090
Accumulated Amortization	(4,726)	(4,817)
Net Carrying Amount	183us-gaap_FiniteLivedIntangibleAssetsNet	273us-gaap_FiniteLivedIntangibleAssetsNet
Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,272	1,278
Accumulated Amortization	(1,107)	(1,084)
Net Carrying Amount	165	194
Contracts Owned Equipment [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,637	3,812
Accumulated Amortization	(3,619)	(3,733)
Net Carrying Amount	$ 18	$ 79

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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