anchor.diff:      <th>Memo</th>
       <th style="text-align: right">Amount</th>
     </tr>
  -  <% 
  -    invoiced_items = Payment.where(invoice_id: @invoice.id).where.not(payable_type: :invoice)
  -    invoiced_items.each do |pmt| %>
  +  <% invoiced_items.each do |pmt| %>
     <tr>
       <%
       if pmt.payable_type == "ShipmentItem"
  -      si = ShipmentItem.find(pmt.payable_id)
  +      si = pmt.payable
       %>
         <td><%= si.shipment.ship_date %></td>
         <td><%= link_to si.shipment.to_s, admin_store_shipment_path(si.shipment) %></td>
  
positive.code:             </td>
            </tr>
            <% end %>
            <tr>
              <td>Status</td>
              <td>
  
negative.code:       <td style="text-align: right"><%= si.quantity %></td>
        
      <% elsif pmt.payable_type == "Shipment" 
          shp = pmt.payable %>
        <td><%= shp.ship_date%></td>
        <td><%= link_to shp.to_s, admin_store_shipment_path(shp) %></td>
        <td><%= pmt.transaction_id %></td>
  