Claims Payable (Details) (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Components of the change in claims payable
Claims payable, beginning of period	$ 510,675	$ 529,036
Health benefits expense incurred during the period:
Related to current year	2,613,310	2,408,166
Related to prior years	(74,588)	(90,149)
Total incurred	2,538,722	2,318,017
Health benefits payments during the period:
Related to current year	2,168,850	1,960,389
Related to prior years	361,039	361,061
Total payments	2,529,889	2,321,450
Claims payable, end of period	$ 519,508	$ 525,603

Total amount of payments made during the reporting period to settle insured claims and pay costs incurred in the claims settlement process.

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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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