// "Drop Menu" for Show/Hide Filter //

function ShowMenu(n) {
	var menu, arrowImg;
	menu = document.getElementById("showHideMenu_" + n);
	// Determine if the menu is currently showing.
	if (menu.style.display == 'block'){
		// If it is showing, hide the menu and update the twisty image.
    menu.style.display = 'none';
    arrowImg = document.images['i' + n];
    arrowImg.src = "img/arrow_right.gif";
  }
	else
  {
  	// Hide all layers first.
    var divs = document.getElementsByTagName("div");
       
    for (var i = 0; i < divs.length; i++)
    	if (divs[i].id.indexOf("showHideMenu_") >= 0)
          divs[i].style.display = 'none';
     
    // Reset the images.
    for (var j = 0; j < document.images.length; j++)
    	if (document.images[j].src.indexOf("arrow_down") > 0)
          document.images[j].src = "img/arrow_right.gif";
       
    // Show the menus and update their twisty images.
    menu = document.getElementById("showHideMenu_" + n);
    arrowImg = document.images["i" + n];
    menu.style.display = "block";
    arrowImg.src = "img/arrow_down.gif";

   }
}