Derivative instruments (Details Textual) (USD $)	6 Months Ended
	Dec. 30, 2012
Derivative Instruments (Textual) [Abstract]
Premiums to be paid and received under the weekly Mexican peso currency option contracts net	$ 0
Currency buy sell under contract one [Member]
Derivative Instruments (Textual) [Abstract]
Mexican peso contract: contract end date	Jul. 06, 2012
Mexican Peso Option Contract - Contractual Exchange Rate	11.85
Currency buy sell under contract two [Member]
Derivative Instruments (Textual) [Abstract]
Mexican peso contract: contract end date	Jul. 06, 2012
Mexican Peso Option Contract - Contractual Exchange Rate	12.85
Currency buy sell under contract three [Member]
Derivative Instruments (Textual) [Abstract]
Mexican Peso Option Contract - Contractual Exchange Rate	12.40
Effective period of additional Mexican peso contract	Contracts that are effective July 6, 2012 through June 28, 2013
Currency buy sell under contract four [Member]
Derivative Instruments (Textual) [Abstract]
Mexican Peso Option Contract - Contractual Exchange Rate	13.40
Effective period of additional Mexican peso contract	Contracts that are effective July 6, 2012 through June 28, 2013