Consolidated Balance Sheet (Parenthetical) (USD $) In Thousands, except Share data	Jul. 31, 2011	Jan. 31, 2011
Consolidated Balance Sheet
Accounts receivable, allowance for doubtful accounts	$ 63,184	$ 56,811
Common stock, par value	$ 0.0015	$ 0.0015
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	59,239,085	59,239,085
Treasury stock, shares	15,842,364	12,517,538