Patents (Details Textual) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Patent amortization expense	$ 87us-gaap_AdjustmentForAmortization	$ 89us-gaap_AdjustmentForAmortization
Patents impairment	$ 0	$ 0

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 3

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16373-109275

Name:	us-gaap_ImpairmentOfIntangibleAssetsFinitelived
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration