docs: function(event, ui){
  
  	    // Prevent default selection input filling action (from
  	    // jQuery UI) when non-default marked.
  	    if( ! anchor._fill_p ){
  		event.preventDefault();		
  	    }
  
  	    var doc_to_apply = null;
  	    if( ui.item ){
  		doc_to_apply = ui.item.document;
  	    }
  
  	    // Only do the callback if it is defined.
  	    if( doc_to_apply && 
  		bbop.core.is_defined(anchor._list_select_callback) ){
  		anchor._list_select_callback(doc_to_apply);
  	    }
  	}