Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Oct. 31, 2012	Jan. 31, 2012
Statement of Financial Position [Abstract]
Accounts receivable, allowance	$ 2,369	$ 2,929
Common stock, par value	$ 0.10	$ 0.10
Common stock, shares authorized	600,000,000	600,000,000
Common stock, shares issued	220,601,756	219,708,779
Common stock, shares outstanding	219,257,343	218,636,842
Treasury stock, shares	1,344,413	1,071,937