Second mRender parameter

I'm getting a reference error that type is not defined; this just started now, as I was trying to eliminate all my in-line functions; any way this could not be an in-line function, since it is used twice in the same exact way?

$('#example').dataTable({
  /* More configuration, */
  'aoColumns': [
    {'mData': 'Field_1'},
    {'mData': 'Field_2'},
    {'mData': 'Field_3'},
    {'mData': 'Field_4', 'mRender': renderData(data, type)},
  ]
});