CRM 2011 Get Owner ID in JavaScript

CRM 2011 Get Owner ID in JavaScript

JavaScript:

function OnLoadForm()
{
    var OwnerId = GetLookup_OwnerId();
}

function GetLookup_OwnerId()
{
   var lookup = new Array();
   lookup = Xrm.Page.getAttribute("ownerid").getValue();
   if (lookup != null) {
      var name = lookup[0].name;
       var id = lookup[0].id;
       var entityType = lookup[0].entityType;
       return id;
   }
}