var domTT_styleClass = 'domTTOverlib';
  	
  	function ShowHide( id , type ){
		var divId = document.getElementById( id );

  		if(type == 'show'){
  			/* make it visible */
			divId.style.position = 'relative';
			divId.style.display = 'block';  			
  		}
  		else if(type == 'hide'){
  			/* let it disappear */
    		divId.style.position = 'absolute';
    		divId.style.display = 'none';
  		}		
		else if(divId.style.display == 'block'){
    		/* let it disappear */
    		divId.style.position = 'absolute';
    		divId.style.display = 'none';
		}else{
			/* make it visible */
			divId.style.position = 'relative';
			divId.style.display = 'block';
		}
	}
	
	
	function isEmpty(s)
	{   return ((s == null) || (s.length == 0))
	}
	
	var globalS = null;
	
	function isValidNumber( s ){
		var nr = s.value;
		var defaultEmptyOK = false;
		
		var reFloat = /^((\d+(\,\d*)?)|((\d*\,)?\d+))$/
		
		if (isEmpty(nr)) 
       		if (isValidNumber.arguments.length == 1) return defaultEmptyOK;
       		else return (isValidNumber.arguments[1] == true);

		if(reFloat.test(nr)==false){
			globalS = s;
			alert('Vul aub geldige getallen in. (Formaat XX of XX,XX)');
			s.focus();
			setTimeout("globalS.focus(); globalS.select()", 0); 
			return false;
		}
		else{
			return true;
		}
       		
	}
	
	function popWindow(url,winName,W,H,X,Y) {
		if(W == undefined) W = 250;	//default width
		if(H == undefined) H = 260; //default height
		if(X == undefined) X = screen.width/2-W/2; //default Xpos (is now centered)
		if(Y == undefined) Y = (screen.height/2)-(H/2); //default Ypos (is now centered)

		winprops = 'height='+H+',width='+W+',top='+Y+',left='+X+',scrollbars=yes';

		win = window.open(url, winName, winprops);
		
		if (parseInt(navigator.appVersion) >= 4) {
			win.window.focus();
		}
	}