Investments - Narrative (Details)	6 Months Ended
	Jul. 27, 2014
Investment [Line Items]
Number of investments in privately held companies	2
Minimum [Member]
Investment [Line Items]
Investment maturity period	3 months
Temporary Investments [Member] | Minimum [Member]
Investment [Line Items]
Investment maturity period	3 months
Temporary Investments [Member] | Maximum [Member]
Investment [Line Items]
Investment maturity period	12 months
Long-Term Investments [Member] | Minimum [Member]
Investment [Line Items]
Investment maturity period	12 months
Long-Term Investments [Member] | Maximum [Member]
Investment [Line Items]
Investment maturity date, fiscal year	2016