v2.4.1.9
Goodwill And Intangible Assets (Narrative) (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended
Jun. 30, 2012
Goodwill and Intangible Assets Disclosure [Abstract]  
Goodwill and intangible asset impairment $ 28us-gaap_GoodwillAndIntangibleAssetImpairment
Impairment of intangible assets (excluding goodwill) 2us-gaap_ImpairmentOfIntangibleAssetsExcludingGoodwill
Goodwill, impairment loss 26us-gaap_GoodwillImpairmentLoss
Nondeductible impairment loss $ 27cnc_NondeductibleImpairmentLoss