Stockholders' Equity - Stock Option Grants, Activity And Expense (Details)	12 Months Ended			24 Months Ended
	Nov. 30, 2018 USD ($) individual $ / shares shares	Nov. 30, 2017 USD ($) $ / shares shares	Nov. 30, 2016 USD ($) $ / shares shares	Nov. 30, 2017 USD ($) $ / shares shares
Unrecognized compensation expense related to non-vested stock options that will be recognized during future periods
Fiscal 2019 | $	$ 265,000
Fiscal 2020 | $	125,000
Fiscal 2021 | $	32,000
Other Disclosures
Total grant date fair value of options vested | $	69,000	$ 55,000	$ 457,000
Exercise of stock options | $				$ 0
Intrinsic value of options exercised | $	$ 765,000
Minimum
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares		$ 11.13
Assumptions used in determining the fair value of the stock options granted
Risk free interest rates (as a percent)		2.10%
Maximum
Assumptions used in determining the fair value of the stock options granted
Risk free interest rates (as a percent)		2.20%
2009 Stock Option Plan
2009 Stock Option Plan
Expiration term	10 years
Number of options that may be exercised as stock appreciation rights	0
Granted (in shares)	5,195	11,570	109,859
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)	30.50%
Risk free interest rates (as a percent)	3.00%
Expected option term (in years)	8 years 6 months
Annual dividend yield (as a percent)	1.10%		0.90%
Other Disclosures
Number of option holders | individual	27
Compensation expense for stock options
Compensation expense (benefit) | $	$ 350,000	$ 349,000	$ 267,000
Related tax benefit (expense) | $	$ 53,000	$ 86,000	$ 62,000
Forfeiture rates (as a percent)	0.00%	0.00%	0.00%
Activity under the 2009 Stock Option Plan
Outstanding at beginning of period (in shares)	333,762	324,546	225,727	225,727
Granted (in shares)	5,195	11,570	109,859
Exercised (in shares)	(94,677)
Forfeited (in shares)	(20,279)	(2,354)	(11,040)
Outstanding at end of period (in shares)	224,001	333,762	324,546	333,762
Weighted Avg. Exercise Price
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 29.22	$ 29.23	$ 30.47	$ 30.47
Granted (in dollars per share) | $ / shares	38.48	30.59	26.83
Exercised (in dollars per share) | $ / shares	31.18
Forfeited (in dollars per share) | $ / shares	33.78	36.82	30.73
Outstanding at end of period (in dollars per share) | $ / shares	$ 28.20	$ 29.22	$ 29.23	$ 29.22
2009 Stock Option Plan | Non-employee directors
2009 Stock Option Plan
Granted (in shares)	5,195	6,570	8,409
Fair values of stock options granted (in dollars per share) | $ / shares	$ 14.41	$ 13.49	$ 11.30
Activity under the 2009 Stock Option Plan
Granted (in shares)	5,195	6,570	8,409
2009 Stock Option Plan | Employee
2009 Stock Option Plan
Granted (in shares)		5,000	101,450
Fair values of stock options granted (in dollars per share) | $ / shares		$ 11.13
Activity under the 2009 Stock Option Plan
Granted (in shares)		5,000	101,450
2009 Stock Option Plan | Minimum
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)		32.70%	32.90%
Risk free interest rates (as a percent)			1.20%
Expected option term (in years)		7 years 6 months	5 years
Annual dividend yield (as a percent)		0.80%
2009 Stock Option Plan | Minimum | Non-employee directors
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares			$ 7.51
2009 Stock Option Plan | Minimum | Executives
Compensation expense for stock options
Forfeiture rates (as a percent)	17.90%	17.90%	17.90%
2009 Stock Option Plan | Minimum | Employee
Compensation expense for stock options
Forfeiture rates (as a percent)	38.30%	38.30%	38.30%
2009 Stock Option Plan | Maximum
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)		39.60%	41.10%
Risk free interest rates (as a percent)			1.50%
Expected option term (in years)		8 years 6 months	8 years 6 months
Annual dividend yield (as a percent)		0.90%
2009 Stock Option Plan | Maximum | Non-employee directors
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares			$ 11.65