Discontinued operations (Details Textuals) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Discontinued Operations [Abstract]
Write-down of assets associated with a discontinued component, net of income tax benefit	$ (268,000)		$ (268,000)
Assets held for sale	650,000		650,000
Discontinued Operation, Revenue	247,000	266,000	465,000	497,000
Losses from operations before income tax benefit related to component	112,000	18,000	241,000	110,000
Loss from operations of a discontinued component, net of income tax benefit	45,000		82,000	33,000
income tax benefit, write down assets associated with discontinued component	$ 138,000		$ 138,000