INVESTMENTS: (Tables)
 6 Months Ended
May. 31, 2015
Investments [Abstract]  
Schedule of carrying amount of investments
The carrying amount of the Company’s investments is shown in the table below: 
 
As of
 
May 31, 2015
 
November 30, 2014
 
Cost Basis
 
Unrealized Gains
 
Carrying
Value
 
Cost Basis
 
Unrealized Gains
 
Carrying
Value
Short-term investments:
 
 
 
 
 
 
 
 
 
 
 
Trading securities
$
—

 
$
—

 
$
—

 
$
1,614

 
$
373

 
$
1,987

Held-to-maturity investments
5,587

 
—

 
5,587

 
5,141

 
—

 
5,141

 
$
5,587

 
$
—

 
$
5,587

 
$
6,755

 
$
373

 
$
7,128

Long-term investments in other assets:
 
 
 
 
 
 
 
 
 
 
 
Available-for-sale securities
$
820

 
$
1,410

 
$
2,230

 
$
843

 
$
897

 
$
1,740

Cost-method investments
$
4,555

 
$
—

 
$
4,555

 
$
4,578

 
$
—

 
$
4,578
Schedule of gains (losses) on trading investments
The following table summarizes the total gains recorded in “Other income (expense), net” in the Consolidated Statements of Operations for changes in the fair value of the Company's trading investments:
 
Three Months Ended
 
Six Months Ended
 
May 31, 2015
 
May 31, 2014
 
May 31, 2015
 
May 31, 2014
Gains (losses) on trading investments
$
(9
)
 
$
255

 
$
50

 
$
314