function div_change(strID){
  for (i=0;i<div_change.arguments.length;i++) {
    var _id = div_change.arguments[i];
    document.getElementById(_id).style.display = (document.getElementById(_id).style.display == 'none' ) ? 'block' : 'none';
    document.getElementById(_id + "_shown").style.display = (document.getElementById(_id + "_shown").style.display == 'none' ) ? 'block' : 'none';
    document.getElementById(_id + "_hidden").style.display = (document.getElementById(_id + "_hidden").style.display == 'none' ) ? 'block' : 'none';
    }
 }