Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jul. 31, 2012	Jan. 31, 2012
Consolidated Balance Sheets [Abstract]
Accumulated depreciation of rental assets	$ 18,342	$ 20,978
Accumulated depreciation of property, equipment and improvements	$ 221,176	$ 215,525
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	75,000,000	75,000,000
Common stock, shares issued	11,944,544	11,944,544
Common stock, shares outstanding	8,218,863	8,292,147
Treasury stock, shares	3,725,681	3,652,397