Mega Nav SetTimeout while scrolling

	var timerShowMenu = null ;
            var $megaMenu = $('.nav_leftcol')
              , $menuItems = $megaMenu.find('.sub_nav')
              , changeSpeed = 50
              , that = this
              , isMenuOpen = false;
			var hideDelay = 500;
            ;$megaMenu.on('mouseenter', '.primary_nav > ul > li', function(evt) {
                if (!isMenuOpen) {
                    timerShowMenu = setTimeout(function() {
                        isMenuOpen = true;
                        //that.showMenu(evt, $megaMenu, $menuItems, changeSpeed);
						$(this).addClass('active');
							if($(this).find('.sub_nav').length != 0) {
							$('body').addClass('main_nav_active');
						}
                    }
                    , hideDelay);
                } else {
                   // that.showMenu(evt, $megaMenu, $menuItems, changeSpeed);
				   $(this).addClass('active');
							if($(this).find('.sub_nav').length != 0) {
							$('body').addClass('main_nav_active');
						}
                }
            }
            );

           // if (!Modernizr.touch) {
                $(document).bind('mouseover', function(evt) {
					var target = (evt.target || evt.srcElement);   
					if (target.nodeType == 3) {
						target = target.parentNode;
					}
                    var isMouseStillInsideMegaMenu = ($(target).closest($megaMenu).length > 0);
                    if (!isMouseStillInsideMegaMenu) {
                        if (timerShowMenu) {
                            clearTimeout(timerShowMenu);
                            timerShowMenu = null ;
                        }
                        //that.hideMenu($megaMenu, $menuItems, changeSpeed);
						 $(this).removeClass('active');
						$('body').removeClass('main_nav_active');
                        isMenuOpen = false;
                    }
                });
            //}