var imgShow = new Image();
var imgHide = new Image();
      	
imgShow.src = 'images/plus.gif';
imgHide.src = 'images/minus.gif';
      	
function Expand(id)
	{
   		if (document.getElementById(id + 'div').style.display == 'block')
      		{
      			document.getElementById(id + 'div').style.display = 'none';
      			document.getElementById(id + 'img').src = imgShow.src;
      		}
      		else
      		{
      			document.getElementById(id + 'div').style.display = 'block';
      			document.getElementById(id + 'img').src = imgHide.src;
	   		}
   	}