FAIR VALUE OF CERTAIN FINANCIAL ASSETS AND LIABILITIES (Details 3) (Level 3, Assets at fair value on recurring basis)	12 Months Ended
	Dec. 31, 2012
Auction Rate Securities: Trading | Minimum | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Maximum rate probability (as a percent)	0.38%
Principal returned probability (as a percent)	86.88%
Default probability (as a percent)	3.77%
Liquidity risk (as a percent)	3.50%
Recovery rate (as a percent)	60.00%
Auction Rate Securities: Trading | Maximum | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Maximum rate probability (as a percent)	1.74%
Principal returned probability (as a percent)	95.69%
Default probability (as a percent)	11.57%
Liquidity risk (as a percent)	3.50%
Recovery rate (as a percent)	60.00%
Auction Rate Securities: Trading | Weighted Average | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Maximum rate probability (as a percent)	0.94%
Principal returned probability (as a percent)	87.98%
Default probability (as a percent)	11.08%
Liquidity risk (as a percent)	3.50%
Recovery rate (as a percent)	60.00%
Auction Rate Securities: Available-for-sale | Minimum | Market comparable bonds
Quantitative information related to the significant unobservable inputs
Market price (as a percent)	71.00%
Auction Rate Securities: Available-for-sale | Maximum | Market comparable bonds
Quantitative information related to the significant unobservable inputs
Market price (as a percent)	76.00%
Auction Rate Securities: Available-for-sale | Weighted Average | Market comparable bonds
Quantitative information related to the significant unobservable inputs
Market price (as a percent)	74.00%
Put Options | Minimum | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Counterparty risk (as a percent)	1.01%
Put Options | Maximum | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Counterparty risk (as a percent)	1.61%
Put Options | Weighted Average | Discounted cash flow
Quantitative information related to the significant unobservable inputs
Counterparty risk (as a percent)	1.20%