function getWindowHeight() {
			var windowHeight=0;
				if (typeof(window.innerHeight)=='number') {
					windowHeight=window.innerHeight;
				}
				else {
					if (document.documentElement&&document.documentElement.clientHeight) {
						windowHeight=document.documentElement.clientHeight;
					}
					else {
						if (document.body&&document.body.clientHeight) {
							windowHeight=document.body.clientHeight;
						}
					}
				}
			return windowHeight;
			}


			function setFooter() {
				if (document.getElementById) {
					var windowHeight=getWindowHeight();
					if (windowHeight>0) {
						
						var contentHeight=document.getElementById('wrapper').offsetHeight;
						var navHeight=document.getElementById('nav').offsetHeight;
						var headerHeight=document.getElementById('header').offsetHeight;
						var footerElement=document.getElementById('footer');
						var footerHeight=footerElement.offsetHeight;
						var totalHeight=contentHeight+footerHeight+navHeight + headerHeight +160
						
						if (totalHeight>windowHeight) {
							footerElement.style.position='absolute';
							footerElement.style.top=totalHeight+'px';
							
						}
						else {
							footerElement.style.position='absolute';
							footerElement.style.top='';
							footerElement.style.bottom='10px';
						}
					}
				}
			}

			window.onload = function() {
			  setFooter();
			}
			
			window.onresize = function() {
			  setFooter();
			}