Consolidated Balance Sheets (Parenthetical) - $ / shares	Jan. 31, 2016	Jan. 31, 2015	Jan. 31, 2014
Common stock, par value (in usd per share)	$ 1	$ 1	$ 1
Common stock, shares authorized	100,000,000	100,000,000	100,000,000
Common stock, shares issued	67,006,000	66,947,000	65,318,000
Treasury stock, shares	30,500,000	28,897,000	28,897,000