Calculations of Basic and Diluted Net Income Per Common Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Apr. 30, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Schedule of Earnings Per Share, Basic and Diluted, by Common Class [Line Items]
Income from continuing operations	$ 19,274	$ 11,747	$ 32,656	$ 22,387
Loss from discontinued operations, net of taxes		(35)		(45)
Net income	$ 19,274	$ 11,712	$ 32,656	$ 22,342
Weighted-average common and common equivalent shares outstanding-Basic	54,705	53,944	54,615	53,721
Effect of dilutive securities:
Weighted-average common and common equivalent shares outstanding-Diluted	55,804	54,963	55,650	54,728
Net income per common share
Basic	$ 0.35	$ 0.22	$ 0.60	$ 0.42
Diluted	$ 0.35	$ 0.21	$ 0.59	$ 0.41
RSUs
Effect of dilutive securities:
Effect of dilutive securities	448	358	435	369
Performance shares
Effect of dilutive securities:
Effect of dilutive securities	353	259	353	280
Stock options
Effect of dilutive securities:
Effect of dilutive securities	298	402	247	358