CONSOLIDATED BALANCE SHEETS (Parentheticals) - USD ($) $ in Thousands	Jan. 31, 2018	Jan. 31, 2017
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and sales discounts on accounts receivable (in dollars)	$ 165,416	$ 155,488
Preferred stock, shares authorized	1,000	1,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	120,000	120,000
Common stock, shares issued	49,219	49,016
Treasury stock, shares	106	376