Reporting Entity - Additional Information (Detail)	12 Months Ended
Dec. 31, 2014
Entity Information [Line Items]
Percentage of premiums and services revenues derived from contracts with Federal Government	73.00%
FLORIDA
Entity Information [Line Items]
Percentage of premiums and services revenue related to contracts with CMS for Medicare Advantage members in Florida	15.00%

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	dei_EntityInformationLineItems
Namespace Prefix:	dei_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration