v2.4.1.9

Income Taxes (Tax Effects Of Temporary Differences Which Give Rise To Deferred Tax Assets And Liabilities) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
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Income Tax Disclosure [Abstract] |  |
Medical claims liability | $ 27 us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities | $ 20 us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccrualsAccruedLiabilities
Accrued expenses | 11 us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals | 5 us-gaap_DeferredTaxAssetsTaxDeferredExpenseReservesAndAccruals
Net operating loss carryforward | 21 us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal | 16 us-gaap_DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal
Compensation accruals | 53 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost | 31 us-gaap_DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefitsShareBasedCompensationCost
Premium and related receivables | 35 cnc_Premiumandrelatedreceivables | 20 cnc_Premiumandrelatedreceivables
Other | 9 us-gaap_DeferredTaxAssetsOther | 16 us-gaap_DeferredTaxAssetsOther
Deferred tax assets | 156 us-gaap_DeferredTaxAssetsGross | 108 us-gaap_DeferredTaxAssetsGross
Valuation allowance | (12)us-gaap_DeferredTaxAssetsValuationAllowance | (8)us-gaap_DeferredTaxAssetsValuationAllowance
Net deferred tax assests | 144 us-gaap_DeferredTaxAssetsNet | 100 us-gaap_DeferredTaxAssetsNet
Intangible assets | 25 us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets | 18 us-gaap_DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets
Prepaid assets | 6 cnc_DeferredTaxLiabilitiesPrepaidAssetsAndOtherCurrent | 6 cnc_DeferredTaxLiabilitiesPrepaidAssetsAndOtherCurrent
Depreciation and amortization | 26 cnc_DeferredTaxLiabilitiesDepreciationAndAmortizationNoncurrent | 30 cnc_DeferredTaxLiabilitiesDepreciationAndAmortizationNoncurrent
Other | 4 us-gaap_DeferredTaxLiabilitiesOther | 2 us-gaap_DeferredTaxLiabilitiesOther
Deferred Tax Liabilities | 61 us-gaap_DeferredIncomeTaxLiabilities | 56 us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax assets | $ 83 us-gaap_DeferredTaxAssetsLiabilitiesNet | $ 44 us-gaap_DeferredTaxAssetsLiabilitiesNet

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- Definition Amount of deferred tax liability attributable to taxable temporary differences. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Deferred Tax Liability -URI http://asc.fasb.org/extlink&oid=6510232 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph b(2) -Article 7 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Deferred Tax Asset -URI http://asc.fasb.org/extlink&oid=6510090 + Details
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- Definition Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards, net of deferred tax liability attributable to taxable temporary differences. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=29652012&loc=d3e28680-109314 + Details
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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from reserves and accruals. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32621-109319 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32632-109319 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 25 -Paragraph 20 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=29652012&loc=d3e28680-109314 + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319 + Details
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