Income Taxes - Liability for Uncertain Tax Positions (Details) (USD $) In Thousands, unless otherwise specified	Jan. 25, 2015	Jan. 26, 2014
Income Tax Contingency [Line Items]
Total accrued taxes	$ 7,774	$ 12,347
Accrued liabilities
Income Tax Contingency [Line Items]
Liability for uncertain tax positions - current	0	0
Noncurrent Deferred Tax Asset [Member]
Income Tax Contingency [Line Items]
Liability for uncertain tax positions - noncurrent	7,522	12,095
Other Liabilities [Member]
Income Tax Contingency [Line Items]
Liability for uncertain tax positions - noncurrent	$ 252	$ 252