function showlay (idname,show,parent) {
	var lay = document.getElementById (idname);
	if (show == 0) var v = "hidden";
	else var v = "visible";
	
	lay.style.visibility = v;
	if (parent > 0) {
	for(i=0;i<parent;i++){
	lay = lay.parentNode;
	lay.style.visibility = v;
	}
	}
}