function showHide(divId, wwwroot){
    theDiv = document.getElementById(divId);
    theIcon = document.getElementById(divId+'_icon');
    if(theDiv.style.display == 'none'){
        theDiv.style.display = 'block';
        theIcon.src = wwwroot+'/blocks/cat_course_list/down.png';
    }else{
        theDiv.style.display = 'none';
        theIcon.src = wwwroot+'/blocks/cat_course_list/up.png';
    }
}