Stock Option Plan and Stock Based Compensation - Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended		12 Months Ended
	Nov. 30, 2017	Nov. 30, 2016	Feb. 28, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Options Outstanding, Beginning Balance	172,496
Number of Shares, Granted	0	0
Number of Shares, Terminated	0
Number of Shares, Exercised	0
Number of Shares, Options Outstanding, Ending Balance	172,496		172,496
Number of Shares, Exercisable	170,880
Weighted Average Exercise Price, Beginning Balance	$ 15.95
Weighted Average Exercise Price, Granted	0
Weighted Average Exercise Price, Terminated	0
Weighted Average Exercise Price, Exercised	0
Weighted Average Exercise Price, Ending Balance	15.95		$ 15.95
Weighted Average Exercise Price, Exercisable	$ 15.97
Weighted Average Remaining Contractual Life (in years)	3 years 6 months		4 years 2 months 12 days
Weighted Average Remaining Contractual Life, Exercisable	3 years 4 months 24 days
Aggregate Intrinsic Value	$ 896		$ 223
Aggregate Intrinsic Value, Exercisable	$ 884