function myGetPageSize()
{
       
	     var xScroll;
		 var yScroll;

		if (window.innerHeight && window.scrollMaxY) {	
			xScroll = window.innerWidth + window.scrollMaxX;
			yScroll = window.innerHeight + window.scrollMaxY;
		} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
			xScroll = document.body.scrollWidth;
			yScroll = document.body.scrollHeight;
		} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
			xScroll = document.body.offsetWidth;
			yScroll = document.body.offsetHeight;
		}
		
		var windowWidth;
		var windowHeight;
		
		if (self.innerHeight) {	// all except Explorer
			if(document.documentElement.clientWidth){
				windowWidth = document.documentElement.clientWidth; 
			} else {
				windowWidth = self.innerWidth;
			}
			windowHeight = self.innerHeight;
		} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
			windowWidth = document.documentElement.clientWidth;
			windowHeight = document.documentElement.clientHeight;
		} else if (document.body) { // other Explorers
			windowWidth = document.body.clientWidth;
			windowHeight = document.body.clientHeight;
		}	
		
		// for small pages with total height less then height of the viewport
		if(yScroll < windowHeight){
			pageHeight = windowHeight;
		} else { 
			pageHeight = yScroll;
		}
	
		// for small pages with total width less then width of the viewport
		if(xScroll < windowWidth){	
			pageWidth = xScroll;		
		} else {
			pageWidth = windowWidth;
		}

		return [pageWidth,pageHeight];
	}




function ToggleInstances()

{
	full=document.getElementById('instances_holder');
	myOverlay=document.getElementById('inst_overlay');
	
	if (full && full.style.display=="block")
	{
		full.style.display="none";
		myOverlay.style.display="none";
	}
	else 
	{
		arrayPageSize = myGetPageSize();
		myOverlay.style.width=arrayPageSize[0]+"px";
		myOverlay.style.height=arrayPageSize[1]+"px";
		full.style.display="block";
		myOverlay.style.display="block";
	}
}

function ToggleCombobox(combo_id)
{
	combo = document.getElementById(combo_id);
	if (combo){
		Effect.toggle(combo_id, 'blind', { duration: 0.5 });

	    //if (combo.style.display=="block") {combo.style.display="none";}
		//else {combo.style.display="block";}
		}

}