Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data	Apr. 30, 2011	Jan. 31, 2011	Apr. 30, 2010
Allowance for doubtful accounts	$ 302	$ 300	$ 300
Common stock, par value	$ 1	$ 1	$ 1
Common stock, shares authorized	100,000	100,000	100,000
Common stock, shares issued	32,528	32,511	32,478
Treasury stock, at cost	14,449	14,449	14,449