Income (Loss) Per Share Information (Details) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2010	Jul. 31, 2010	Apr. 30, 2010	Jan. 31, 2010	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2009
Income (Loss) Per Share Information (Details) [Abstract]
Basic weighted-average shares	166,896	168,075	166,910	166,677	166,269	165,752	165,407	165,237	167,140	165,666	161,549
Common stock equivalents									1,241
Diluted weighted-average shares	167,525	169,338	166,910	168,121	167,777	167,658	165,407	165,237	168,381	165,666	161,549
Common stock equivalents excluded from diluted weighted-average shares due to anti-dilutive effect										1,968	3,936
Weighted average number of anti-dilutive options									7,936	8,401	7,604
Shares issued under stock incentive and employee stock purchase plans									2,390	1,712	4,442