Stockholders' Equity - Stock Option Grants, Activity And Expense (Details) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 31, 2018 USD ($) individual $ / shares shares	Aug. 31, 2017 USD ($) $ / shares shares	Aug. 31, 2018 USD ($) individual $ / shares shares	Aug. 31, 2017 USD ($) $ / shares shares
Other Disclosures
Number of option holders | individual	28		28
Compensation expense for stock options
Compensation expense (benefit) | $	$ 83	$ 90	$ 261	$ 260
Related tax benefit (expense) | $	14	$ 19	40	$ 59
Unrecognized compensation expense related to non-vested stock options that will be recognized during future periods
Balance of Fiscal 2018 | $	89		89
Fiscal 2019 | $	265		265
Fiscal 2020 | $	125		125
Fiscal 2021 | $	$ 32		$ 32
2009 Stock Option Plan
2009 Stock Option Plan
Expiration term			10 years
Granted (in shares)			5,195	11,570
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%
Activity under the 2009 Stock Option Plan
Outstanding at beginning of period (in shares)			333,762	324,546
Granted (in shares)			5,195	11,570
Exercised (in shares)			(74,554)
Forfeited (in shares)			(20,279)	(2,354)
Outstanding at end of period (in shares)	244,124	333,762	244,124	333,762
Weighted Avg. Exercise Price
Outstanding at beginning of period (in dollars per share) | $ / shares			$ 29.22	$ 29.23
Granted (in dollars per share) | $ / shares			38.48	30.59
Exercised (in dollars per share) | $ / shares			31.97
Forfeited (in dollars per share) | $ / shares			33.78	36.82
Outstanding at end of period (in dollars per share) | $ / shares	$ 28.20	$ 29.22	$ 28.20	$ 29.22
Other Disclosures
Number of options that may be exercised as stock appreciation rights	0		0
2009 Stock Option Plan | Non-employee directors
2009 Stock Option Plan
Granted (in shares)			5,195	6,570
Fair values of stock options granted (in dollars per share) | $ / shares			$ 14.41	$ 13.49
Compensation expense for stock options
Forfeiture rates (as a percent)			0.00%	0.00%
Activity under the 2009 Stock Option Plan
Granted (in shares)			5,195	6,570
2009 Stock Option Plan | Executives
Compensation expense for stock options
Forfeiture rates (as a percent)			17.90%	17.90%
2009 Stock Option Plan | Employee
2009 Stock Option Plan
Granted (in shares)				5,000
Fair values of stock options granted (in dollars per share) | $ / shares				$ 11.13
Compensation expense for stock options
Forfeiture rates (as a percent)			38.30%	38.30%
Activity under the 2009 Stock Option Plan
Granted (in shares)				5,000
Minimum | 2009 Stock Option Plan
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)			30.50%	32.70%
Risk free interest rates (as a percent)			3.00%	2.10%
Expected option term (in years)				7 years 6 months
Annual dividend yield (as a percent)			1.10%	0.80%
Maximum | 2009 Stock Option Plan
Assumptions used in determining the fair value of the stock options granted
Expected volatility (as a percent)				39.60%
Risk free interest rates (as a percent)				2.20%
Expected option term (in years)				8 years 6 months
Annual dividend yield (as a percent)				0.90%