function toggle_cluetip_ids(id_on, id_off) {
    // toggle ids found inside a cluetip
    if ($('#simplemodal-container').find('#'+id_on).length == 1) {
      $('#simplemodal-container').find('#'+id_off).css("display","none");
      $('#simplemodal-container').find('#'+id_on).css("display","block");
    } else {
      // must not be in a cluetip
      // @TODO: verify that this detection works
      $('#'+id_off).css("display","none");
      $('#'+id_on).css("display","block");
    }
}