Assets and liabilities measured at fair value (Details) $ in Thousands	Oct. 30, 2015 USD ($)
Reported amount | Current portion of long-term debt obligations
Liabilities:
Long-term obligations	$ 1,358
Reported amount | Long-term obligations
Liabilities:
Long-term obligations	3,105,332
Reported amount | Accrued expenses and other current liabilities
Liabilities:
Deferred compensation	5,984
Reported amount | Noncurrent Other liabilities
Liabilities:
Deferred compensation	18,297
Fair value measurements on recurring basis | Balance at the end of the period
Liabilities:
Long-term obligations	3,100,145
Deferred compensation	24,281
Fair value measurements on recurring basis | Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)
Liabilities:
Long-term obligations	2,276,411
Deferred compensation	24,281
Fair value measurements on recurring basis | Significant Other Observable Inputs (Level 2)
Liabilities:
Long-term obligations	$ 823,734