The controller that I have created is :

public class CandidateList {

    Candidate__c candidate ;
    public Candidate__c getCandidate() {
        Id id = ApexPages.currentPage().getParameters().get('id');
       
        candidate = [Select Id, Name from Candidate__c
where id = :ApexPages.currentPage().getParameters().get('id')];
return candidate;
    }

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and the page that i developed

<apex:page Controller="CandidateList">
<apex:pageBlock title="Hello {!$User.FirstName}!">
You are displaying Candidates List.
Mouse over a Candidate's name to view his or her details.
</apex:pageBlock>
<apex:pageBlock title="Candidates">
<apex:form >
<apex:dataTable value="{!candidate}" var="contact" cellPadding="4"
border="1">
<apex:column >
<apex:outputPanel >
<apex:actionSupport event="onmouseover" rerender="detail">
<apex:param name="cid" value="{candidate__c.id}"/>
</apex:actionSupport>
{!contact.Name}
</apex:outputPanel>
</apex:column>
</apex:dataTable>
</apex:form>
</apex:pageBlock>
<apex:outputPanel id="detail">
<apex:actionStatus startText="Requesting...">
<apex:facet name="stop">
<apex:detail subject="{!$CurrentPage.parameters.cid}" relatedList="false"
title="false"/>
</apex:facet>
</apex:actionStatus>
</apex:outputPanel>
</apex:page>


Can any one suggest y I am getting Insufficient privileges when I am putting mouse on the value to get the detail