Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net earnings	$ 487,063	$ 543,105	$ 438,616
Adjustments to reconcile net earnings to cash provided by operating activities:
Depreciation and amortization	152,859	136,865	140,685
Amortization of stock compensation	29,643	40,530	40,532
Deferred income tax provision / (benefit)	27,896	35,760	(27,364)
RADV Release	(132,977)	0	0
RADV Release – deferred tax adjustment	50,531	0	0
Provider class action – (release) / charge	0	(159,300)	278,000
Provider class action – deferred tax adjustment	0	58,145	(103,385)
Other adjustments	(27,731)	13,968	18,586
Changes in assets and liabilities, net of effects of the purchase of subsidiaries:
Provider class action – settlement	0	(150,500)	0
Accounts receivable, net	22,508	7,287	(2,389)
Other receivables, net	(168,479)	(198,479)	(2,399)
Medical liabilities	57,073	68,272	(439,265)
Accounts payable and other accrued liabilities	(76,561)	68,605	(46,174)
Other changes in assets and liabilities	48,819	(63,099)	(23,191)
Net cash from operating activities	470,644	401,159	272,252
Cash flows from investing activities:
Capital expenditures, net	(89,064)	(62,085)	(63,257)
Proceeds from sales of investments	1,367,133	1,790,877	561,457
Proceeds from maturities of investments	247,524	261,753	573,625
Purchases of investments	(1,595,596)	(2,584,935)	(819,808)
Payments for acquisitions, net	(54,945)	(7,616)	(102,356)
Net cash from investing activities	(124,948)	(602,006)	149,661
Cash flows from financing activities:
Proceeds from issuance of stock	87,671	44,624	15,484
Payments for repurchase of stock	(339,985)	(336,219)	(4,888)
Proceeds from issuance of debt, net	0	589,867	0
Repayment of debt	(233,903)	(380,029)	0
Excess tax benefit from stock compensation	12,210	7,619	2,925
Payments for cash dividends	(51,530)	0	0
Net cash from financing activities	(525,537)	(74,138)	13,521
Net change in cash and cash equivalents	(179,841)	(274,985)	435,434
Cash and cash equivalents at beginning of period	1,579,003	1,853,988	1,418,554
Cash and cash equivalents at end of period	1,399,162	1,579,003	1,853,988
Supplemental disclosure of cash flow information:
Cash paid for interest	102,238	91,875	77,973
Income taxes paid, net	$ 175,511	$ 264,556	$ 471,479