XML 27 R30.htm IDEA: XBRL DOCUMENT v2.4.0.6
FAIR VALUE MEASUREMENTS (Details) (USD $)
3 Months Ended
Mar. 31, 2013
Mar. 31, 2013
Notes Receivable [Member]
Mar. 31, 2013
Carrying Value [Member]
Dec. 31, 2012
Carrying Value [Member]
Mar. 31, 2013
Fair Value [Member]
Quoted prices in active markets (Level 1) [Member]
Dec. 31, 2012
Fair Value [Member]
Quoted prices in active markets (Level 1) [Member]
Mar. 31, 2013
Fair Value [Member]
Significant other observable inputs (Level 2) [Member]
Dec. 31, 2012
Fair Value [Member]
Significant other observable inputs (Level 2) [Member]
Mar. 31, 2013
Fair Value [Member]
Significant unobservable inputs (Level 3) [Member]
Dec. 31, 2012
Fair Value [Member]
Significant unobservable inputs (Level 3) [Member]
Assets carried at fair value measured on a recuring basis [Abstract]                    
Cash equivalents     $ 36,063,000 $ 63,863,000 $ 36,063,000 $ 63,863,000 $ 0 $ 0 $ 0 $ 0
Short-term investments     175,311,000 158,018,000 175,311,000 154,018,000 0 0 0 4,000,000
Long-term investments     4,868,000 1,270,000 568,000 970,000 0 0 4,300,000 300,000
Impairment of non-marketable convertible debt 0                  
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]                    
Fair value of notes, beginning of period 4,300,000                  
Investments   0                
Fair value of notes, end of period $ 4,300,000