SUBSEQUENT EVENTS (Details) (Subsequent Event [Member])	Dec. 31, 2012
Subsequent Event [Member]
Subsequent Event [Line Items]
Kentucky contract rate (in hundredths)	7.00%

Effective January 1, 2013, the increase to the Company’s Kentucky Medicaid contract rates for each of the contract years remaining under the initial term of the contract.

No definition available.

Name:	cvh_KentuckyContractRate
Namespace Prefix:	cvh_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant