Stockholders' Equity (Details 3) (2009 Stock Option Plan, USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Feb. 28, 2015
Griffin Stock Option Plan
Outstanding at ending of the year (in shares)	222,001
Weighted Avg. Exercise Price (in dollars per share)	$ 30.35
Weighted Avg. Remaining Contractual Life	5 years
Total Intrinsic Value	$ 511
$23.00-$28.00
Griffin Stock Option Plan
Exercise prices, low end of range (in dollars per share)	$ 23.00
Exercise prices, high end of range (in dollars per share)	$ 28.00
Outstanding at ending of the year (in shares)	18,068
Weighted Avg. Exercise Price (in dollars per share)	$ 25.45
Weighted Avg. Remaining Contractual Life	5 years 8 months 12 days
Total Intrinsic Value	121
$28.00-$32.00
Griffin Stock Option Plan
Exercise prices, low end of range (in dollars per share)	$ 28.00
Exercise prices, high end of range (in dollars per share)	$ 32.00
Outstanding at ending of the year (in shares)	120,858
Weighted Avg. Exercise Price (in dollars per share)	$ 28.90
Weighted Avg. Remaining Contractual Life	5 years 10 months 24 days
Total Intrinsic Value	$ 390
$32.00-$39.00
Griffin Stock Option Plan
Exercise prices, low end of range (in dollars per share)	$ 32.00
Exercise prices, high end of range (in dollars per share)	$ 39.00
Outstanding at ending of the year (in shares)	83,075
Weighted Avg. Exercise Price (in dollars per share)	$ 33.52
Weighted Avg. Remaining Contractual Life	3 years 7 months 6 days