checkbox pass to input field has conflict in jquery

I'm trying to add the value of the checkbox in the field the is closest to it. But I think I missed something. Please see my code below:

$(document).ready(function(){
    $("input:checkbox").click(function() {
        var output = "";
        $("input:checked").each(function() {
            output += $(this).val() + " ";
        });
        
        $(this).closest('.divs').find("#field_results").val(output.trim());
        
    });
});

<script src="http://ift.tt/1oMJErh"></script>
<div class="divs">
  <input type="text" id="field_results"/><br>

  <input type="checkbox" value="1">1<br>
  <input type="checkbox" value="2">2<br>
  <input type="checkbox" value="3">3
</div>

<br><br>

<div class="divs">
  <input type="text" id="field_results"/><br>
  <input type="checkbox" value="1">1<br>
  <input type="checkbox" value="2">2<br>
  <input type="checkbox" value="3">3
</div>