General - Per Member Per Month Revenue (Details) - Minimum	3 Months Ended
Mar. 31, 2018
Operating results by business segment
Term of PMPM contract	1 year
Required notice to terminate PMPM contract	30 days

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.

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration