How do I modify data before getData()?

I would like to remove all id attributes before getData() returns data to the user.

I am currently trying to remove the id attributes on beforeGetData and the getData events:

editor.on('beforeGetData', function(e){

    e.editor.undoManager.lock();

    var ids = e.editor.element.find('[id]');

    for(i = 0; i < ids.count(); i++){
        ids.getItem(i).removeAttribute('id');
    }

    e.editor.undoManager.unlock();
});

editor.on('getData', function(e){

    e.editor.undoManager.lock();

    var ids = e.editor.element.find('[id]');

    for(i = 0; i < ids.count(); i++){
        ids.getItem(i).removeAttribute('id');
    }

    e.data.dataValue = e.editor.getData(true);
    e.editor.undoManager.unlock();
});

However, in all cases, it appears that getData() returns old data even after modification to the dom. How can I remove all id attributes before returning data?