A quick note on the detach() method..

If the selector you use with detach() doesn't match any element in the dom, then JQuery will still return an object.

(function($){

	$(document).ready(function(){
		
		var obj = $("#someDivThatDoesntExist").detach();
		
		alert(obj); 
		// shows that obj is an Object
		
		alert(obj.length);
		// shows that the length is 0 
		// (I could swear this returned 1 in an earlier version of jQuery)
		
		alert(obj[0]);
		// undefined
	});

})(jQuery);