Line Of Credit Facility - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended					1 Months Ended								12 Months Ended
	Oct. 31, 2011	Nov. 30, 2010	Oct. 31, 2010	Oct. 31, 2011 Minimum	Oct. 31, 2011 Maximum	Sep. 08, 2011 Second Amendment	Nov. 30, 2010 Second Amendment	Nov. 30, 2010 Second Amendment Minimum	Nov. 30, 2010 Second Amendment Maximum	Nov. 30, 2010 LIBOR Second Amendment Minimum	Nov. 30, 2010 LIBOR Second Amendment Maximum	Nov. 30, 2010 Alternate Base Rate Second Amendment Minimum	Nov. 30, 2010 Alternate Base Rate Second Amendment Maximum	Oct. 31, 2011 Interest Rate Swap	Oct. 31, 2011 Forward starting swaps
Line of Credit Facility [Line Items]
Terminated existing line of credit borrowing capacity		$ 450
Syndicated line of credit, maximum capacity		650.0
Syndicated line of credit, optional maximum capacity at any time prior to the expiration (subject to receipt of commitments for the increased amount from existing and new lenders)		850
Syndicated line of credit facility, expiration date						2016-09-08
Variable Rate										1.00%	1.75%	0.00%	0.75%
Percentage of commitment fee on the unused portion of the Facility								0.225%	0.30%
Frequency of non-use fee payable									quarterly
Line of credit, interest rate terms							Based on the Company's leverage ratio (as defined in the new Facility), the Interbank Offered Rate plus a spread of 1.00% to 1.75% or, at the Company's election, base rate loans plus a spread of 0% to 0.75%. The Facility calls for a non-use fee, based on the leverage ratio, payable quarterly, in arrears, of 0.225% to 0.300% of the average daily unused portion of the Facility.
Description of covenants under the Facility	(1) a fixed charge coverage ratio greater than or equal to 1.50 to 1.0 at any time; (2) a leverage ratio of less than or equal to 3.25 to 1.0 at each fiscal quarter-end; and (3) a consolidated net worth of greater than or equal to the sum of (i) $570.0 million, (ii) an amount equal to 50% of the consolidated net income earned in each full fiscal quarter ending after November 30, 2010 (with no deduction for a net loss in any such fiscal quarter), and (iii) an amount equal to 100% of the aggregate increases in stockholders’ equity of the Company after November 30, 2010 by reason of the issuance and sale of capital stock or other equity interests of the Company or any subsidiary, including upon any conversion of debt securities of the Company into such capital stock or other equity interests, but excluding by reason of the issuance and sale of capital stock pursuant to the Company’s employee stock purchase plans, employee stock option plans and similar programs
Consolidated net worth	570.0
Consolidated net income earned	50.00%
Aggregate increases in stockholders' equity	100.00%
Fixed charge coverage ratio				1.5
Leverage ratio					3.25
Line of credit, amount outstanding	300.0
Standby letters of credit	96.8		100.8
Derivative agreement date														Feb. 19, 2009	Oct. 19, 2010
Description of derivative agreement														Entered into a two-year interest rate swap agreement with an underlying notional amount of $100.0 million, pursuant to which the Company received variable interest payments based on LIBOR and paid fixed interest at a rate of 1.47%. This interest rate swap expired on February 19, 2011.	Entered into a three-year forward starting interest rate swap agreement with an underlying notional amount of $25.0 million, pursuant to which the Company receives variable interest payments based on LIBOR and pays fixed interest at a rate of 0.89%.
Notional amount of derivatives														100.0	25.0
Derivative, fixed interest rate														1.47%	0.89%
Derivative, effective date															Feb. 24, 2011
Derivative, effective date														Feb. 19, 2011
Fair value of interest rate swaps														0.3
Effective portion of cash flow hedges included in accumulated other comprehensive loss, before tax														(0.3)
Effective portion of cash flow hedges included in accumulated other comprehensive loss, net of tax														$ 0.2