Consolidated Statements Of Stockholders' Equity And Comprehensive Income (USD $) In Thousands, unless otherwise specified	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings
Beginning Balance at Oct. 31, 2009	$ 687,050	$ 517	$ 176,480	$ (2,423)	$ 512,476
Beginning Balance (in shares) at Oct. 31, 2009		51,688
Comprehensive income:
Net income	64,121				64,121
Unrealized gain (loss) on auction rate securities, net of taxes of $866 in 2012, $193 in 2011 and $179 in 2010	461			461
Reclassification adjustment for credit losses recognized in earnings, net of taxes of $126 in 2012 and $53 in 2010	74			74
Foreign currency translation	68			68
Actuarial gain (loss) - Adjustments to pension and other post-retirement benefit plans, net of taxes of $594 in 2012, $996 in 2011 and $108 in 2010	(381)			(381)
Unrealized gain (loss) on interest rate swaps, net of taxes of $230	338			338
Comprehensive income	64,681
Dividends:
Common stock	(28,152)				(28,152)
Tax effect from exercise of stock options	383		383
Stock issued under employees' stock purchase and option plans (in shares)		947
Stock issued under employees' stock purchase and option plans	10,992	9	11,484		(501)
Share-based compensation expense	4,071		4,071
Ending Balance at Oct. 31, 2010	739,025	526	192,418	(1,863)	547,944
Ending Balance (in shares) at Oct. 31, 2010		52,635
Comprehensive income:
Net income	68,504				68,504
Unrealized gain (loss) on auction rate securities, net of taxes of $866 in 2012, $193 in 2011 and $179 in 2010	306			306
Foreign currency translation	214			214
Net unrealized gain on interest rate swaps, net of taxes of $16 in 2012 and $76 in 2011	115			115
Actuarial gain (loss) - Adjustments to pension and other post-retirement benefit plans, net of taxes of $594 in 2012, $996 in 2011 and $108 in 2010	(1,433)			(1,433)
Comprehensive income	67,706
Dividends:
Common stock	(29,744)				(29,744)
Tax effect from exercise of stock options	(467)		(467)
Stock issued under employees' stock purchase and option plans (in shares)		698
Stock issued under employees' stock purchase and option plans	10,175	7	10,247		(79)
Share-based compensation expense	9,191		9,191
Ending Balance at Oct. 31, 2011	795,886	533	211,389	(2,661)	586,625
Ending Balance (in shares) at Oct. 31, 2011		53,333
Comprehensive income:
Net income	62,582				62,582
Unrealized gain (loss) on auction rate securities, net of taxes of $866 in 2012, $193 in 2011 and $179 in 2010	1,244			1,244
Reclassification adjustment for credit losses recognized in earnings, net of taxes of $126 in 2012 and $53 in 2010	187			187
Foreign currency translation	(85)			(85)
Net unrealized gain on interest rate swaps, net of taxes of $16 in 2012 and $76 in 2011	23			23
Actuarial gain (loss) - Adjustments to pension and other post-retirement benefit plans, net of taxes of $594 in 2012, $996 in 2011 and $108 in 2010	(862)			(862)
Comprehensive income	63,089
Dividends:
Common stock	(31,309)				(31,309)
Tax effect from exercise of stock options	(156)		(156)
Stock issued under employees' stock purchase and option plans (in shares)		1,061
Stock issued under employees' stock purchase and option plans	12,652	11	13,167		(526)
Share-based compensation expense	10,236		10,236
Ending Balance at Oct. 31, 2012	$ 850,398	$ 544	$ 234,636	$ (2,154)	$ 617,372
Ending Balance (in shares) at Oct. 31, 2012		54,394