INVESTMENTS (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Investments
Unrealized losses	$ 1,200,000
Adjusted Cost	3,670,000	5,319,000
Unrealized gains	83,000	31,000
Unrealized losses	0	(20,000)
Net unrealized (losses) gains	83,000	11,000
Tax Excluded from Net Unrealized Gains	0	0
Fair value of investment	3,753,000	5,330,000
Amount included in short-term investments	2,687,000	3,079,000
Auction-rate securities	1,066,000	2,251,000
Contractual maturities (at adjusted cost) of available-for-sale debt securities
Due within one year	0
Due in 1-5 years	0
Due in 5-10 years	0
Due after 10 years	983,000
Total	983,000
Minimum maturity period of short-term investments as company has the ability and intent to redeem them within the year (in days)	90 days
Corporate equity securities
Investments
Adjusted Cost	2,687,000	0
Fair value of investment	2,687,000	0
Auction-rate securities
Investments
Adjusted Cost	983,000	2,220,000
Fair value of investment	1,066,000	2,251,000
Corporate debt securities and other obligations
Investments
Adjusted Cost	0	3,099,000
Fair value of investment	$ 0	$ 3,079,000