Earnings Per Share Information (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Apr. 30, 2018	Apr. 30, 2017	Apr. 30, 2018	Apr. 30, 2017	Sep. 05, 2012
Earnings Per Share [Abstract]
Net income as reported	$ 111,810	$ 124,638	$ 243,917	$ 195,054
Interest and costs attributable to 0.5% Exchangeable Senior Notes, net of income tax benefit		385		769
Numerator for diluted earnings per share	$ 111,810	$ 125,023	$ 243,917	$ 195,823
Basic weighted-average shares	152,731	163,492	154,306	163,040
Common stock equivalents	2,398	2,051	2,707	2,011
Shares attributable to 0.5% Exchangeable Senior Notes		5,860		5,859
Diluted weighted-average shares	155,129	171,403	157,013	170,910
Debt Instrument [Line Items]
Shares issued under stock incentive and employee stock purchase plans	57	694	880	1,974
Restricted Stock Units RSU And Employee Stock Option Member [Member]
Debt Instrument [Line Items]
Weighted-average number of antidilutive options and restricted stock units	278	1,865	823	3,535
0.5% Exchangeable Senior Notes Due 2032 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					0.50%