//tested on mozilla and ie 6.0, 7.0
function flipStyle(s) { return s == "none" ? "block" : "none"; }
function showHide(id) { 
	if (document.layers) {
		document.layers[id].display = flipStyle(document.layers[id].display);
	} else if (document.all) {
		document.all[id].style.display = flipStyle(document.all[id].style.display);
	} else if (document.getElementById) {
		document.getElementById(id).style.display = flipStyle(document.getElementById(id).style.display);
	}
}