Consolidated Statements Of Operations (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues
Health plan services premiums	$ 3,720,800	$ 2,881,345
Government contracts	154,714us-gaap_ContractsRevenue	144,090us-gaap_ContractsRevenue
Net investment income	13,241us-gaap_InvestmentIncomeNet	11,102us-gaap_InvestmentIncomeNet
Administrative services fees and other income	1,141	2,398
Total revenues	3,889,896us-gaap_Revenues	3,038,935us-gaap_Revenues
Expenses
Health plan services (excluding depreciation and amortization)	3,142,863	2,402,342
Government contracts	142,540us-gaap_ContractRevenueCost	131,974us-gaap_ContractRevenueCost
General and administrative	453,848us-gaap_GeneralAndAdministrativeExpense	361,023us-gaap_GeneralAndAdministrativeExpense
Selling	68,696us-gaap_SellingExpense	64,152us-gaap_SellingExpense
Depreciation and amortization	4,307us-gaap_DepreciationAndAmortization	9,663us-gaap_DepreciationAndAmortization
Interest	8,049us-gaap_InterestExpense	7,821us-gaap_InterestExpense
Asset impairment	1,884us-gaap_AssetImpairmentCharges	0us-gaap_AssetImpairmentCharges
Total expenses	3,822,187us-gaap_OperatingExpenses	2,976,975us-gaap_OperatingExpenses
Income from operations before income taxes	67,709	61,960
Income tax provision	37,721us-gaap_IncomeTaxExpenseBenefit	33,173us-gaap_IncomeTaxExpenseBenefit
Net income	$ 29,988us-gaap_NetIncomeLoss	$ 28,787us-gaap_NetIncomeLoss
Net income per share:
Basic (usd per share)	$ 0.39us-gaap_EarningsPerShareBasic	$ 0.36us-gaap_EarningsPerShareBasic
Diluted (usd per share)	$ 0.38us-gaap_EarningsPerShareDiluted	$ 0.36us-gaap_EarningsPerShareDiluted
Weighted average shares outstanding:
Basic (shares)	77,085	79,802
Diluted (shares)	78,370	80,922

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