Nature Of Business And Summary Of Significant Accounting Policies (Correction of Prior Period Amounts (Income Statement)) (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Nov. 30, 2012	Aug. 31, 2012	May 31, 2012	Feb. 29, 2012	Nov. 30, 2011	Aug. 31, 2011	May 31, 2011	Feb. 28, 2011	Nov. 30, 2012	Nov. 30, 2011	Nov. 30, 2010
Provision for income taxes (in dollars)									$ 17,032	$ 34,380	$ 32,666
Income from continuing operations (in dollars)	10,775	5,353	4,527	11,949	17,221	14,426	18,432	16,263	32,604	66,342	62,568
Loss from discontinued operations (in dollars)									14,840	(6,713)	(14,470)
Net income	36,025	5,838	(1,908)	7,489	12,175	9,059	17,919	20,476	47,444	59,629	48,098
Basic:
Continuing operations per share, basic	$ 0.17	$ 0.08	$ 0.07	$ 0.19	$ 0.27	$ 0.22	$ 0.28	$ 0.24	$ 0.52	$ 1.01	$ 0.98
Discontinued operations per share, basic									$ 0.24	$ (0.10)	$ (0.23)
Net income per share, basic									$ 0.75	$ 0.91	$ 0.75
Diluted:
Continuing operations per share, diluted	$ 0.17	$ 0.08	$ 0.07	$ 0.19	$ 0.27	$ 0.21	$ 0.27	$ 0.23	$ 0.51	$ 0.98	$ 0.94
Discontinued operations per share, diluted									$ 0.23	$ (0.10)	$ (0.22)
Net income per share, diluted									$ 0.74	$ 0.88	$ 0.73
As Previously Reported [Member]
Provision for income taxes (in dollars)										28,943	22,857
Income from continuing operations (in dollars)					0	0	0	0		0	0
Loss from discontinued operations (in dollars)											0
Net income					11,679	8,601	17,960	20,521		58,761	48,571
Basic:
Continuing operations per share, basic					$ 0.00	$ 0.00	$ 0.00	$ 0.00		$ 0.00	$ 0.00
Discontinued operations per share, basic											$ 0.00
Net income per share, basic										$ 0.89	$ 0.76
Diluted:
Continuing operations per share, diluted					$ 0.00	$ 0.00	$ 0.00	$ 0.00		$ 0.00	$ 0.00
Discontinued operations per share, diluted											$ 0.00
Net income per share, diluted										$ 0.87	$ 0.73
Impact of Discontinued Operations [Member]
Provision for income taxes (in dollars)										6,305	9,565
Income from continuing operations (in dollars)					16,725	13,968	18,473	16,308		65,474	62,812
Loss from discontinued operations (in dollars)											(14,241)
Net income					0	0	0	0		0	0
Basic:
Continuing operations per share, basic					$ 0.27	$ 0.21	$ 0.28	$ 0.24		$ 1.00	$ 0.98
Discontinued operations per share, basic											$ (0.22)
Net income per share, basic										$ 0.00	$ 0.00
Diluted:
Continuing operations per share, diluted					$ 0.26	$ 0.21	$ 0.27	$ 0.23		$ 0.97	$ 0.95
Discontinued operations per share, diluted											$ (0.22)
Net income per share, diluted										$ 0.00	$ 0.00
Adjustment [Member]
Provision for income taxes (in dollars)										(868)	244
Income from continuing operations (in dollars)					496	458	(41)	(45)		868	(244)
Loss from discontinued operations (in dollars)											(229)
Net income					$ 496	$ 458	$ (41)	$ (45)		$ 868	$ (473)
Basic:
Continuing operations per share, basic					$ 0.01	$ 0.01	$ 0.00	$ 0.00		$ 0.01	$ 0.00
Discontinued operations per share, basic											$ 0.00
Net income per share, basic										$ 0.01	$ (0.01)
Diluted:
Continuing operations per share, diluted					$ 0.01	$ 0.01	$ 0.00	$ 0.00		$ 0.01	$ 0.00
Discontinued operations per share, diluted											$ 0.00
Net income per share, diluted										$ 0.01	$ (0.01)