Annual report pursuant to Section 13 and 15(d)

CASH, CASH EQUIVALENTS AND AVAILABLE-FOR-SALE SECURITIES (Details)

v2.4.0.8
CASH, CASH EQUIVALENTS AND AVAILABLE-FOR-SALE SECURITIES (Details) (USD $)
 3 Months Ended 12 Months Ended
Jun. 30, 2013
Dec. 31, 2013
item
Dec. 31, 2012
item
Dec. 31, 2011
Dec. 31, 2010
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   $ 211,975,000 $ 298,241,000    
Cash and cash equivalents   20,854,000 33,484,000 18,633,000 8,877,000
Available-for-sale securities   191,121,000 264,757,000    
Cash equivalents and available-for-sale securities          
Amortized Cost   202,674,000 273,972,000    
Gross Unrealized Gains   64,000 135,000    
Gross Unrealized Losses   (17,000) (53,000)    
Fair Value   202,721,000 274,054,000    
Years to Maturity          
Within One Year   181,846,000      
After One Year Through Two Years   20,875,000      
Weighted-average time to maturity of cash equivalents and available-for-sale securities   159 days      
Stated maturity period may be greater than this period and classified as current   1 year      
Proceeds from sale of available-for-sale securities 16,500,000 16,479,000      
Number of investments in continuous unrealized loss position for more than twelve months   4 0    
Investments in unrealized loss position for more than twelve months   2,000      
Fair value and gross unrealized losses of investments in individual securities in unrealized loss position          
Number of individual securities in unrealized loss position for twelve months or less   12      
Fair Value   31,255,000      
Unrealized Losses   (17,000)      
Money market funds
          
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   9,059,000 23,936,000    
U. S. treasury bills
          
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   2,085,000      
Cash equivalents and available-for-sale securities          
Amortized Cost   2,083,000      
Gross Unrealized Gains   2,000      
Fair Value   2,085,000      
Years to Maturity          
After One Year Through Two Years   2,085,000      
Government-sponsored enterprise securities
          
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   67,178,000 77,047,000    
Cash equivalents and available-for-sale securities          
Amortized Cost   67,160,000 77,041,000    
Gross Unrealized Gains   29,000 37,000    
Gross Unrealized Losses   (11,000) (31,000)    
Fair Value   67,178,000 77,047,000    
Years to Maturity          
Within One Year   49,394,000      
After One Year Through Two Years   17,784,000      
Fair value and gross unrealized losses of investments in individual securities in unrealized loss position          
Fair Value   7,989,000      
Unrealized Losses   (11,000)      
Corporate bonds and commercial paper
          
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   133,458,000 197,007,000    
Cash equivalents and available-for-sale securities          
Amortized Cost   133,431,000 196,931,000    
Gross Unrealized Gains   33,000 98,000    
Gross Unrealized Losses   (6,000) (22,000)    
Fair Value   133,458,000 197,007,000    
Years to Maturity          
Within One Year   132,452,000      
After One Year Through Two Years   1,006,000      
Fair value and gross unrealized losses of investments in individual securities in unrealized loss position          
Fair Value   23,266,000      
Unrealized Losses   (6,000)      
Checking account
          
Cash, cash equivalents and available-for-sale securities          
Cash, cash equivalents and available-for-sale securities   $ 195,000 $ 251,000