Shareholders' Equity (Details 3) $ / shares in Units, $ in Millions	12 Months Ended
	Jan. 28, 2017 USD ($) $ / shares shares
Shareholders Equity
Number of Shares	228,682
Restricted share and restricted share unit awards
Shareholders Equity
Unrecognized compensation expense related to unvested share-based restricted stock awards and the unvested restricted share units (in dollars) | $	$ 7.1
Restricted share units
Shareholders Equity
Number of Shares	33,780
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 60
Restricted share units | Fiscal 2014
Shareholders Equity
Number of Shares	24,751
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 78
Performance shares
Shareholders Equity
Number of Shares	30,000
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 76
Performance shares | Fiscal 2014
Shareholders Equity
Number of Shares	65,196
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 78
Performance shares | Fiscal 2015
Shareholders Equity
Number of Shares	73,361
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 58
Performance shares | Fiscal 2016
Shareholders Equity
Number of Shares	31,594
Average Market Price on Date of Grant (in dollars per share) | $ / shares	$ 76