Rule to deselect checkbox item?
if you wont find any other solution without coding to deselect that checkbox you can try to do it via your custom module (if you don't have any you will have to make one - that's different story). 

function YOUR_MODULE_NAME_form_alter(&amp;$form, &amp;$form_state, $form_id){
  $form['field_order_details']['und']['0']['value']['#resizable'] = FALSE;
}


Something similar should work for your checkbox.

See hook_form_alter().