function toggle_visibility(id,tog) {
   var e = document.getElementById(id);
   if(e.style.display == 'block'){
	  e.style.display = 'none';
	  tog.innerHTML = 'expand';
   }  else {
	  e.style.display = 'block';
	  tog.innerHTML = 'collapse';
   }
}

function gup( name )
{
  name = name.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
  var regexS = "[\\?&]"+name+"=([^&#]*)";
  var regex = new RegExp( regexS );
  var results = regex.exec( window.location.href );
  if( results == null )
    return "";
  else
    return results[1];
}

function expand() {
	var show = gup( 'show' );
	if (show == '') { return "" }
	else { 
		document.getElementById(show).style.display = 'block';
		document.getElementById('tog_'+show).innerHTML = 'collapse';
	}
}