"columns" => array(
            "business_component",
            "last_date_modified"=>array("label"=>"date of document"),
            "reason"=>array("label"=>"reason for inclusion"),
            "description"=>array("label"=>"description of document"),
            "thumbnail_url" => array("label"=>"substantiation",
                "formatValue"=> "<img width='500px' height='400px' src='".base_url()."/@value' />"
            ),

when a user clicks on the thumbnail_url image, I'd like to send them to the full file in another window or tab. How would I add the link to the formatValue?

Thx.