v2.4.1.9

Discontinued Operations Discontinued Operations (Assets & Liabilities) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2014 | Dec. 31, 2013
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Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |
Assets of Disposal Group, Including Discontinued Operation, Current | $ 75 us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent | $ 78 us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperationCurrent
Disposal Group, Including Discontinued Operations, Long Term Investments and Restricted Deposits | 25 cnc_DisposalGroupIncludingDiscontinuedOperationsLongTermInvestmentsandRestrictedDeposits | 38 cnc_DisposalGroupIncludingDiscontinuedOperationsLongTermInvestmentsandRestrictedDeposits
Disposal Group, Including Discontinued Operation, Other Noncurrent Assets | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets | 0 us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentAssets
Assets of Disposal Group, Including Discontinued Operation | 100 us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation | 116 us-gaap_AssetsOfDisposalGroupIncludingDiscontinuedOperation
Disposal Group, Including Discontinued Operations, Medical Claims Liability | 10 cnc_DisposalGroupIncludingDiscontinuedOperationsMedicalClaimsLiability | 27 cnc_DisposalGroupIncludingDiscontinuedOperationsMedicalClaimsLiability
Disposal Group, Including Discontinued Operation, Accounts Payable and Accrued Liabilities | 7 us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities | 3 us-gaap_DisposalGroupIncludingDiscontinuedOperationAccountsPayableAndAccruedLiabilities
Disposal Group, Including Discontinued Operation, Other Noncurrent Liabilities | 1 us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities | 1 us-gaap_DisposalGroupIncludingDiscontinuedOperationOtherNoncurrentLiabilities
Liabilities of discontinued operations | $ 18 us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation | $ 31 us-gaap_LiabilitiesOfDisposalGroupIncludingDiscontinuedOperation

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- Definition Disposal Group, Including Discontinued Operations, Long Term Investments and Restricted Deposits + References No definition available. + Details
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- Definition Disposal Group, Including Discontinued Operations, Medical Claims Liability + References No definition available. + Details
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- Definition Amount classified as assets attributable to disposal group held for sale or disposed of. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759 + Details
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- Definition Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759 + Details
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- Definition Amount classified as accounts payable and accrued liabilities attributable to disposal group held for sale or disposed of. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
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- Definition Amount classified as other assets attributable to disposal group held for sale or disposed of, expected to be disposed of after one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
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- Definition Amount classified as other liabilities attributable to disposal group held for sale or disposed of, expected to be disposed of beyond one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760 + Details
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- Definition Amount classified as liabilities attributable to disposal group held for sale or disposed of. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 45 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 205 -SubTopic 20 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760 + Details
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