SEGMENT INFORMATION (Details) (USD $) In Thousands, 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 segments	Dec. 31, 2011	Dec. 31, 2010
Segment Reporting [Abstract]
Number of reportable segments											3
Operating revenues:
Managed care premiums											12,926,375	$ 11,014,950	$ 10,414,640
Management services											1,186,988	1,171,733	1,173,276
Total operating revenues	3,445,817	3,457,783	3,517,796	3,691,967	[1]	3,129,156	2,975,543	3,033,046	[2]	3,048,938	14,113,363	12,186,683	11,587,916
Medical costs											10,853,774	9,041,402	8,265,947
Cost of sales											266,803	283,544	252,052
Gross margin											2,992,786	2,861,737	3,069,917
Selling, general and administrative											2,080,236	2,016,042	1,961,947
Provider class action - (release) / charge											0	(159,300)	278,000
Depreciation and amortization											152,859	136,865	140,685
Operating earnings	178,534	159,478	145,203	276,476	[1]	148,943	192,613	355,101	[2]	171,473	759,691	868,130	689,285
Commercial Products Division [Member]
Operating revenues:
Managed care premiums											5,737,626	6,053,178	5,564,834
Management services											429,209	387,949	418,221
Total operating revenues											6,166,835	6,441,127	5,983,055
Medical costs											4,649,073	4,891,471	4,323,704
Cost of sales											0	0	0
Gross margin											1,517,762	1,549,656	1,659,351
Government Programs Division [Member]
Operating revenues:
Managed care premiums											7,236,240	4,990,770	4,851,756
Management services											0	0	0
Total operating revenues											7,236,240	4,990,770	4,851,756
Medical costs											6,252,192	4,178,929	3,944,193
Cost of sales											0	0	0
Gross margin											984,048	811,841	907,563
Workers' Compensation [Member]
Operating revenues:
Managed care premiums											0	0	0
Management services											757,779	783,784	755,055
Total operating revenues											757,779	783,784	755,055
Medical costs											0	0	0
Cost of sales											266,803	283,544	252,052
Gross margin											490,976	500,240	503,003
Elimination [Member]
Operating revenues:
Managed care premiums											(47,491)	(28,998)	(1,950)
Management services											0	0	0
Total operating revenues											(47,491)	(28,998)	(1,950)
Medical costs											(47,491)	(28,998)	(1,950)
Cost of sales											0	0	0
Gross margin											0	$ 0	$ 0

[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.