Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Per Share data, unless otherwise specified	Oct. 31, 2011	Jan. 31, 2011
Trade accounts receivable, allowance for doubtful accounts	$ 3,773	$ 3,941
Property, plant, and equipment, accumulated depreciation	276,355	257,576
Intangible assets, accumulated amortization	$ 168,714	$ 156,481
Common stock, no par value	$ 0	$ 0
Common stock, shares authorized	300,000	300,000
Common stock, shares issued	109,332	111,249
Common stock, shares outstanding	109,332	111,249
Incentive stock, no par value	$ 0	$ 0
Incentive stock, shares authorized	1,200	1,200
Incentive stock, issued	0	0