Stockholders' Equity - Stock Option Grants, Activity And Expense (Details)	12 Months Ended			24 Months Ended	36 Months Ended
	Nov. 30, 2017 USD ($) individual $ / shares shares	Nov. 30, 2016 USD ($) $ / shares shares	Nov. 30, 2015 USD ($) $ / shares shares	Nov. 30, 2017 USD ($) individual $ / shares shares	Nov. 30, 2017 USD ($) individual $ / shares shares
Unrecognized compensation expense related to non-vested stock options that will be recognized during future periods
Fiscal 2018 | $	$ 340,000			$ 340,000	$ 340,000
Fiscal 2019 | $	234,000			234,000	234,000
Fiscal 2020 | $	112,000			112,000	112,000
Fiscal 2021 | $	34,000			34,000	$ 34,000
Other Disclosures
Total grant date fair value of options vested | $	$ 55,000	$ 457,000	$ 492,000
Exercise of stock options | $				$ 0
Intrinsic value of options exercised | $			$ 18,000
2009 Stock Option Plan
2009 Stock Option Plan
Number of shares authorized	386,926	109,859	8,282	386,926	386,926
Expiration term	10 years
Granted (in shares)	11,570	109,859	8,282
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)			40.80%
Range of risk free interest rate (as a percent)			2.00%
Expected option term (in years)			8 years 6 months
Annual dividend yield (as a percent)		0.90%	0.70%
Other Disclosures
Number of option holders | individual	31			31	31
Compensation expense for stock options
Compensation expense (benefit) | $	$ 349,000	$ 267,000	$ 230,000
Related tax benefit (expense) | $	$ 86,000	$ 62,000	$ 61,000
Forfeiture rates (as a percent)					0.00%
Activity under the 2009 Stock Option Plan
Outstanding at beginning of period (in shares)	324,546	225,727	222,001	225,727	222,001
Granted (in shares)	11,570	109,859	8,282
Exercised (in shares)			(3,134)
Forfeited (in shares)	(2,354)	(11,040)	(1,422)
Outstanding at end of period (in shares)	333,762	324,546	225,727	333,762	333,762
Weighted Avg. Exercise Price
Outstanding at beginning of period (in dollars per share) | $ / shares	$ 29.23	$ 30.47	$ 30.35	$ 30.47	$ 30.35
Granted (in dollars per share) | $ / shares	30.59	26.83	31.38
Exercised (in dollars per share) | $ / shares			25.53
Forfeited (in dollars per share) | $ / shares	36.82	30.73	28.12
Outstanding at end of period (in dollars per share) | $ / shares	$ 29.22	$ 29.23	$ 30.47	$ 29.22	$ 29.22
Other Disclosures
Number of options that may be exercised as stock appreciation rights	0			0	0
2009 Stock Option Plan | Employee
2009 Stock Option Plan
Number of shares authorized		101,450
Granted (in shares)	5,000
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
2009 Stock Option Plan | Non-employee directors
2009 Stock Option Plan
Number of shares authorized		8,409	8,282
Granted (in shares)	6,570
Fair values of stock options granted (in dollars per share) | $ / shares	$ 13.49	$ 11.30	$ 14.39
Activity under the 2009 Stock Option Plan
Granted (in shares)	6,570
Minimum
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares		$ 7.51
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)		32.90%
Range of risk free interest rate (as a percent)		1.20%
Expected option term (in years)		5 years
Minimum | Employee
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares	$ 11.13
Minimum | 2009 Stock Option Plan
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)	32.70%
Range of risk free interest rate (as a percent)	2.10%
Expected option term (in years)	7 years 6 months
Annual dividend yield (as a percent)	0.80%
Minimum | 2009 Stock Option Plan | Executives
Compensation expense for stock options
Forfeiture rates (as a percent)					17.90%
Minimum | 2009 Stock Option Plan | Employee
Compensation expense for stock options
Forfeiture rates (as a percent)					38.30%
Maximum
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares		$ 11.65
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)		41.10%
Range of risk free interest rate (as a percent)		1.50%
Expected option term (in years)		8 years 6 months
Maximum | 2009 Stock Option Plan
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)	39.60%
Range of risk free interest rate (as a percent)	2.20%
Expected option term (in years)	8 years 6 months
Annual dividend yield (as a percent)	0.90%
Maximum | 2009 Stock Option Plan | Executives
Compensation expense for stock options
Forfeiture rates (as a percent)					22.60%
Maximum | 2009 Stock Option Plan | Employee
Compensation expense for stock options
Forfeiture rates (as a percent)					41.10%