Issues with FormData Being Null?

I'm seeming to have an issue with FormData being null. I'm trying to upload files and JSON in a single POST request. I've tried a variety of things, but nothing has seemed to work. I'm wondering if I've messed something basic up here, but I can't seem to find anything. Your help is greatly appreciated!

<form id="uploadCSVWithData" method="post" enctype="multipart/form-data">
    <div class="fileUpload btn btn-info">
        <i class="fa fa-cloud-upload" aria-hidden="true"></i>Upload CSV File <input type="file" name="csvUploadFile" class="upload" />
    </div>
    <input type="text" class="form-control" name="distName" id="distName"></br>
    <input type="text" class="form-control" name="columnNames" id="columnNames"></br>
    <input type="text" class="form-control" name="columnPrices" id="columnPrices"></br>
    <input type="text" class="form-control" name="columnCases" id="columnCases"></br>
    <input type="text" class="form-control" name="columnIds" id="columnIds">
</form>

And Javascript:

event.preventDefault();
var prices = $("#columnPrices").val();
var id = $("#columnIds").val();
var names = $("#columnNames").val();
var distName = $("#distName").val();
var cases = $("#columnCases").val();
var json = {
    columnPrices: prices,
    columnIds: id,
    columnNames: names,
    columnDistName: distName,
    columnCases: cases
}
var data = new FormData($("#uploadCSVWithData"));

console.log("Data is " + JSON.stringify(data))
$(this).html('<i class="fa fa-spinner fa-spin" aria-hidden="true">');
$.ajax({
    type: "POST",
    url: '{removed}',
    data: {
        json: json,
        formData: data
    },
    success: function(done) {
        $("#submitCSVForUpload").html("Submit");
        $("#uploadFromCSVModal").modal('hide');
    },
    processData: false,
    contentType: false
});