Income Taxes (Details) (USD $)	3 Months Ended
	Feb. 28, 2013	Feb. 29, 2012	Nov. 30, 2012
Income Tax Disclosure [Abstract]
Income tax expense	$ (100,000)	$ (400,000)
Net Increase (reduction) in valuation allowance	(700,000)	18,300,000
Net deferred tax assets	0		0
Valuation allowance	879,400,000		880,100,000
Additions (reductions) in total gross unrecognized tax benefits	100,000
Additions to gross unrecognized tax benefits	0
Total amount of unrecognized tax benefits, including interest and penalties	1,400,000
Minimum
Income Tax Contingency [Line Items]
Anticipated decrease in unrecognized tax benefit during 12 months following current reporting date	700,000
Maximum
Income Tax Contingency [Line Items]
Anticipated decrease in unrecognized tax benefit during 12 months following current reporting date	$ 1,100,000