Assets and liabilities measured at fair value (Details) (USD $) In Thousands, unless otherwise specified	May 01, 2015	Jan. 30, 2015
Accrued expenses and other current liabilities
Liabilities:
Derivative financial instruments	$ 263	$ 1,173
Reported amount | Current portion of long-term debt obligations
Liabilities:
Long-term obligations	101,309
Reported amount | Long-term obligations
Liabilities:
Long-term obligations	2,614,005
Reported amount | Accrued expenses and other current liabilities
Liabilities:
Deferred compensation	3,894
Reported amount | Noncurrent Other liabilities
Liabilities:
Deferred compensation	20,788
Fair value measurements on recurring basis | Balance at the end of the period
Liabilities:
Long-term obligations	2,707,519
Deferred compensation	24,682
Fair value measurements on recurring basis | Balance at the end of the period | Accrued expenses and other current liabilities
Liabilities:
Derivative financial instruments	263
Fair value measurements on recurring basis | Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)
Liabilities:
Long-term obligations	1,789,996
Deferred compensation	24,682
Fair value measurements on recurring basis | Significant Other Observable Inputs (Level 2)
Liabilities:
Long-term obligations	917,523
Derivative financial instruments	$ 263