Shareholders’ Equity - 2000 Employee Stock Purchase Plan (Details) - the ESPP - USD ($) $ / shares in Units, shares in Millions, $ in Millions	12 Months Ended
	Jan. 28, 2017	Jan. 30, 2016	Jan. 31, 2015	Feb. 02, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum subscription rate	15.00%
Look-back period	24 months
Offering period	24 months
Percentage discount of purchase price per share of common shares	85.00%
Purchase period				6 months
Number of shares issued	2.3	5.9	9.7
Weighted-average price (in usd per share)	$ 7.33	$ 10.00	$ 7.67
Unamortized compensation expense	$ 16.2
Number of shares available for future issuance	29.5