Income Taxes (Details Textual) (USD $)	3 Months Ended	12 Months Ended
	Nov. 30, 2009	Nov. 30, 2011	Nov. 30, 2010	Nov. 30, 2009	Nov. 30, 2008
Income Taxes (Textual) [Abstract]
Income tax benefit		$ 2,400,000	$ 7,000,000	$ 209,400,000
Valuation allowance loss for the year			26,600,000
Recognition of federal income tax benefit			5,400,000	190,700,000
Reversal of liability for Unrecognized tax benefits		2,600,000	1,600,000	16,300,000
Income taxes refunded		213,000	196,868,000	242,418,000
Net Increase in valuation allowance recorded against net deferred tax assets		76,700,000	21,100,000	67,500,000
Federal income tax benefit from increased carryback of company's net operating loss to offset earnings			5,400,000
Gross Decrease in valuation allowance	196,300,000
Net Decrease in valuation allowance				128,800,000
Non cash income tax benefits reflected to accumulated other comprehensive income	130,700,000
Non cash income tax charge to accumulated other comprehensive income	1,900,000
Valuation allowance against net deferred tax assets	89,900,000		26,600,000	89,900,000
Period for Carry forward of tax benefits related to deferred tax assets		20 years
Expiration year of federal NOL carryforward		2030
Minimum expiration period for state NOLs		2 years
Maximum expiration period for state NOLs		20 years
Total deferred tax assets		161,569,000	165,044,000
Valuation allowance		(847,827,000)	(771,080,000)
Goss unrecognized tax benefits		2,800,000
Goss unrecognized tax benefits	11,024,000	1,899,000	11,308,000	11,024,000	18,332,000
Uncertain tax positions		1,000,000	7,900,000
Unrecognized tax benefits that if recognized would affect the Company's annual effective tax rate	1,300,000	900,000	900,000	1,300,000
Total accrued interest and penalties related to unrecognized income tax benefits		900,000	3,500,000
Maximum [Member]
Income Tax Contingency [Line Items]
Anticipated Decrease in unrecognized tax benefit during 12 months following current reporting date		1,500,000
Tax Credit Carryforward, Expiration Dates		20 years
Minimum [Member]
Income Tax Contingency [Line Items]
Anticipated Decrease in unrecognized tax benefit during 12 months following current reporting date		$ 1,000,000
Tax Credit Carryforward, Expiration Dates		5 years