Shareholders' Equity (Narrative) (Details) (USD $)	1 Months Ended	3 Months Ended	12 Months Ended						1 Months Ended
	Jun. 30, 2013	May 31, 2012	Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2011 Director [Member]	Nov. 30, 2013 Deferred Stock Unit [Member]	Nov. 30, 2011 Deferred Stock Unit [Member]	Jan. 29, 2014 Subsequent Event [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares issued			0	0
Preferred stock, shares outstanding			0
Common stock, shares authorized			200,000,000	200,000,000
Common stock, par value (in dollars per share)			$ 0.01	$ 0.01
Common stock, shares issued			51,512,595	59,594,961
Common stock, shares outstanding			51,512,595	59,594,961
Issuance of shares to Board of Directors, shares						31,000
Issuance of shares to Board of Directors, fair value						$ 700,000
Deferred stock units, shares outstanding							74,900
Deferred stock unit represents common stock, share							1
Deferred stock units granted in period, shares								21,700
Vested restricted stock, shares							12,799
Share repurchase program, authorized amount	360,000,000.0	350,000,000							100,000,000.0
Increase in common stock repurchase amount	10,000,000.0
Common stock repurchased and retired			(11,579,000)	(4,494,000)	(8,391,000)
Common stock repurchased and retired, value (in dollars)			$ 269,469,000	$ 88,384,000	$ 200,009,000