Stockholders' Equity (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended			3 Months Ended												12 Months Ended
	Apr. 08, 2014	Mar. 25, 2014	Jan. 29, 2013	Nov. 30, 2014	Aug. 31, 2014	May 31, 2014	Feb. 28, 2014	Nov. 30, 2013	Aug. 31, 2013	May 31, 2013	Feb. 28, 2013	Nov. 30, 2012	Aug. 31, 2012	May 31, 2012	Feb. 29, 2012	Nov. 30, 2014	Nov. 30, 2013	Nov. 30, 2012	Jul. 18, 2013	Jul. 17, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized				290,000,000				290,000,000								290,000,000	290,000,000
Common Stock, Capital Shares Reserved for Future Issuance				12,602,735												12,602,735
Authorized repurchase of common stock				4,000,000												4,000,000
Common Stock, Shares, Issued				115,386,512				115,296,395								115,386,512	115,296,395
Treasury Stock, Value				$ 446,476				$ 718,565								$ 446,476	$ 718,565
Stockholder's Equity (Textual) [Abstract]
Number of shares that can be purchased by exercising each right				0.01												0.01
Purchase price for right holders				$ 85.00												$ 85.00
Exercisable options available																earlier of (a) 10 calendar days after a public announcement by us that a person or group has become an Acquiring Person (as defined under the 2009 Rights Agreement) and (b) 10 business days after the commencement of a tender or exchange offer by a person or group if upon consummation of the offer the person or group would beneficially own 4.9% or more of our outstanding common stock.
Calendar days after a public announcement during which rights to be exercised																10 days
Business days after the commencement of a tender or exchange offer during which rights to be exercised																10 days
Beneficially ownership in company's outstanding common stock to be held by person or group to exercise rights																4.90%
Price at which company may redeem all of the then outstanding rights				0.001												0.001
Stock Issued During Period, Shares, New Issues	1,041,666	6,944,445	6,325,000
Common stock, par value, in dollars		$ 1.00	$ 1.00	$ 1.00				$ 1.00								$ 1.00	$ 1.00
Treasury Stock Acquired, Average Cost Per Share		$ 18.00	$ 18.25
Stock Issued During Period, Shares, Treasury Stock Reissued			6,325,000			7,986,111
Options under which right issued pursuant to the 2009 rights Agreement will expire																earliest of (a) the close of business on March 5, 2019, (b) the time at which the rights are redeemed, (c) the time at which the rights are exchanged, (d) the time at which our board of directors determines that a related provision in our Restated Certificate of Incorporation is no longer necessary, and (e) the close of business on the first day of a taxable year of ours to which our board of directors determines that no tax benefits may be carried forward. At our annual meeting of stockholders on April 2, 2009, our stockholders approved the 2009 Rights Agreement.
Cash dividend declared per share				$ 0.025	$ 0.025	$ 0.025	$ 0.0250	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.025	$ 0.0625
Stock repurchases																(546)	(8,488)	(1,799)
Proceeds from issuance of common stock, net																137,045	109,503	0
Director Stock Units [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Non-Option Equity Instruments, Outstanding, Number																			481,554
Authorized repurchase of common stock																			482,000
Common Stock, Shares, Issued																			478,294
Treasury Stock, Value																			$ 7,900
Director Plan SARs [Domain]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized																				680,000
Common Stock, Capital Shares Reserved for Future Issuance																				679,815
Authorized repurchase of common stock																				680,000