Fair value measurement Summary of the Non-Financial Assets Measured at Fair Value on Nonrecurring Basis (Details) (Fair Value, Measurements, Nonrecurring, USD $) In Thousands, unless otherwise specified	Dec. 29, 2013	Dec. 30, 2012
Estimate of Fair Value, Fair Value Disclosure
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - Quarter 4	$ 395,851	$ 17,508
Goodwill - Quarter 4	21,790	29,610
Fair Value, Inputs, Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - Quarter 4	0	0
Goodwill - Quarter 4	0	0
Fair Value, Inputs, Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - Quarter 4	0	0
Goodwill - Quarter 4	0	0
Fair Value, Inputs, Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets held for sale - Quarter 4	395,851	17,508
Goodwill - Quarter 4	$ 21,790	$ 29,610

Fair value measurement Summary of the Non-Financial Assets Measured at Fair Value on Nonrecurring Basis (Details) (Fair Value, Measurements, Nonrecurring, USD $)
In Thousands, unless otherwise specified

Dec. 29, 2013

Dec. 30, 2012

Estimate of Fair Value, Fair Value Disclosure

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]

Assets held for sale - Quarter 4

$ 395,851

$ 17,508

Goodwill - Quarter 4

21,790

29,610

Fair Value, Inputs, Level 1

Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]