var tt = null;

function showTT(id) {
	hideTT();
	tt = document.getElementById(id);
	tt.style.display = 'block';
}
function hideTT() {
	if (tt != null) {
		tt.style.display = 'none';
	}
}
function updateTT(e) {
	if (tt != null) {
		x = (document.all) ? window.event.x + tt.offsetParent.scrollLeft : e.pageX;
		y = (document.all) ? window.event.y + tt.offsetParent.scrollTop  : e.pageY;
		tt.style.left = x + 'px';
		tt.style.top   = (y + 25) + 'px';
	}
}
document.onmousemove = updateTT;