Income taxes (Tables)

3 Months Ended

Apr. 29, 2017

Income Tax Disclosure [Abstract]

Reconciliation Of Effective Tax Rate

	13 weeks ended
	April 29, 2017		April 30, 2016
Forecasted annual effective tax rate	23.0	%	26.7	%
Discrete items recognized	0.6	%	—	%
Effective tax rate recognized in income statement	23.6	%	26.7	%