function getElement(id) {
    if (document.getElementById(id) != null) return document.getElementById(id);
    else if (document.all != null) return document.all[id];
    else if (document.layers != null) return document.layers[id];
    else return null;
}

function SetVisibility(id, show) {
    getElement(id).style.display = (show ? 'block': 'none');
}

function showElement(layer){
	var myLayer = getElement(layer);
	SetVisibility(layer, myLayer.style.display == "none");
}