Accrued expenses and other current liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 28, 2012	Dec. 30, 2011
Accrued expenses and other current liabilities [Abstract]
Income taxes payable	$ 6,631	$ 7,047
Accrued compensation	9,242	10,553
Accrued restructuring costs	733	4,157
Deposit on pending divestitures	6,100	0
Other accrued expenses	21,491	23,178
Total accrued expenses and other current liabilities	$ 44,197	$ 44,935