(function($) {
  $.fn.toggleFade = function(settings) {
    settings = jQuery.extend({
        speedIn: "normal",
        speedOut: settings.speedIn
        }, settings
    );
    return this.each( function() {
      var isHidden = jQuery(this).is(":hidden");
      jQuery(this)[ isHidden ? "fadeIn" : "fadeOut" ]( isHidden ? settings.speedIn : settings.speedOut);
    });
  };
})(jQuery);

$(document).ready( function() {
    var invoiceSameInformation = "#new_participants_invoice_same_information";
    
    $(invoiceSameInformation + ":checked").each( function() {
        $("input[name^='new_participants_invoice_']").not(invoiceSameInformation).parent().parent().hide();
    });
    
    $(invoiceSameInformation).bind("change", function(e) {
        $("input[name^='new_participants_invoice_']").not(invoiceSameInformation).parent().parent().toggleFade("slow");
    });
});