Change an element's id using jQuery  

<script>
  $(document).ready(function(){
    //This will set the id to 'americanCurrency'
    $("#usaCurrency").attr("id", "americanCurrency");

    //Now you can perform operations on the element using the new id, 
    //for instance, set the color of the element to blue
    $("#americanCurrency").css({"color": "blue", "border": "2px solid blue"});
});
</script>

A preferred option is to use prop() instead of attr()

<script>
  ...
  $("#usaCurrency").prop("id", "americanCurrency");
  ...
</script>