EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended										12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012		Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011		Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Basic earnings per common share
Net earnings	$ 119,341	$ 105,259	$ 91,743	$ 170,719	[1]	$ 85,696	$ 122,681	$ 224,495	[2]	$ 110,233	$ 487,063	$ 543,105	$ 438,616
Less: Distributed and undistributed earnings allocated to participating securities											(5,571)	(8,038)	(6,592)
Net earnings allocable to common shares											481,492	535,067	432,024
Basic weighted average common shares outstanding											136,042,000	144,775,000	146,169,000
Basic earnings per common share (in dollars per share)	$ 0.89	$ 0.79	$ 0.65	$ 1.21	[1]	$ 0.60	$ 0.84	$ 1.51	[2]	$ 0.74	$ 3.54	$ 3.70	$ 2.96
Diluted earnings per common share
Net earnings	119,341	105,259	91,743	170,719	[1]	85,696	122,681	224,495	[2]	110,233	487,063	543,105	438,616
Less: Distributed and undistributed earnings allocated to participating securities											(5,545)	(7,979)	(6,564)
Net earnings allocable to common shares											$ 481,518	$ 535,126	$ 432,052
Basic weighted average common shares outstanding											136,042,000	144,775,000	146,169,000
Effect of dilutive options											736,000	1,098,000	651,000
Diluted weighted average common shares outstanding											136,778,000	145,873,000	146,820,000
Diluted earnings per common share (in dollars per share)	$ 0.88	$ 0.78	$ 0.65	$ 1.20	[1]	$ 0.60	$ 0.83	$ 1.50	[2]	$ 0.73	$ 3.52	$ 3.67	$ 2.94
Basic earnings per share decrease after retro application of two class method												$ 0.05	$ 0.04
Diluted earnings per share decrease after retro application of two class method												$ 0.03	$ 0.03
Potential common stock equivalents excluded from computation of computation of diluted earnings per share (in shares)											5,600,000	6,500,000	10,000,000

[1] During the quarter ended March 31, 2012, CMS announced which contract years are subject to the CMS RADV audits and other core areas of the audit methodology. As a result of these changes, the Company recorded a non-recurring pre-tax adjustment to earnings of $133.0 million during the first quarter of 2012. See Note A, Organization and Summary of Significant Accounting Policies, to the consolidated financial statements for additional information.

[2] On May 27, 2011, the court entered an order of final approval of a settlement and, accordingly, the Company recorded a non-recurring pre-tax adjustment that increased earnings of $159.3 million in the second quarter of 2011.