Income taxes (Details) (USD $)	9 Months Ended
	Sep. 28, 2013
Income Tax Disclosure [Abstract]
Valuation Allowance, Deferred Tax Asset, Change in Amount	$ 3,600,000
Deferred Tax Assets, Valuation Allowance	7,200,000
Deferred Tax Assets, Net, Noncurrent	(622,000)
Operating Loss Carryforwards	$ 39,400,000