OTHER DISCLOSURES (Details) (USD $)	3 Months Ended
	Mar. 31, 2013 M	Mar. 31, 2012	Dec. 31, 2012
Other income, net [Abstract]
Interest income	$ 16,500,000	$ 18,400,000
Gain on sales of investments	12,500,000	4,300,000
Other income	1,300,000	1,700,000
Other income, net	30,330,000	24,434,000
Concentration of Credit Risk [Abstract]
Premium receivable from State of Illinois	17,100,000		32,200,000
Health Insurance Premiums Outstanding in Months	3
Health Insurance Premiums Outstanding in Months (VAP)	4
Pharmacy rebate receivables	$ 302,500,000		$ 305,400,000
Percent of premiums owed by State of Illinois	100.00%
Percent of premiums owed by State of Illinois after VAP	10.00%