Stock-Based Compensation (Narrative) (Details) (USD $)	3 Months Ended		9 Months Ended
	Aug. 31, 2013	Aug. 31, 2012	Aug. 31, 2013	Aug. 31, 2012 Executives
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,573,000	$ 7,744,000	$ 16,360,000	$ 21,504,000
Number of executives whose employment was terminated				3
Additional stock-based compensation expenses related to separation and acceleration vesting (in dollars)				1,800,000
Stock Options [Member] | Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation award service period (in years)			4 years
Stock Options [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation award service period (in years)			5 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation award service period (in years)			3 years
Accelerated Vesting [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 800,000		$ 1,400,000