var timer = 0;
var shown = false

function showdropdown() {
	clearTimeout(timer);
	if (!shown) {
		document.getElementById('businesstypes').className = 'shown';
		shown = true;
	}
}

function triggerTimer() {
	timer = setTimeout("hidedropdown()", 150);
}

function hidedropdown() {
	document.getElementById('businesstypes').className = '';
	shown = false;
}