v2.4.1.9

Goodwill And Intangible Assets (Schedule Of Changes In Goodwill By Operating Segment) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended |
--- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Goodwill [Line Items] |  |  |
Goodwill | $ 754 us-gaap_Goodwill | $ 348 us-gaap_Goodwill | $ 256 us-gaap_Goodwill
Goodwill, Acquired During Period | 406 us-gaap_GoodwillAcquiredDuringPeriod | 92 us-gaap_GoodwillAcquiredDuringPeriod |
Medicaid Managed Care [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill | 276 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_ManagedCareMember | 151 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_ManagedCareMember | 151 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_ManagedCareMember
Goodwill, Acquired During Period | 125 us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = cnc_ManagedCareMember | 0 us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = cnc_ManagedCareMember |
Specialty Services [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill | 478 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_SpecialtyServicesMember | 197 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_SpecialtyServicesMember | 105 us-gaap_Goodwill / us-gaap_StatementBusinessSegmentsAxis = cnc_SpecialtyServicesMember
Goodwill, Acquired During Period | $ 281 us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = cnc_SpecialtyServicesMember | $ 92 us-gaap_GoodwillAcquiredDuringPeriod / us-gaap_StatementBusinessSegmentsAxis = cnc_SpecialtyServicesMember |

X
- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 + Details
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X
- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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Period Type: | duration

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- Details
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- Details
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X
- Details
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