-A hashref. For each line item this hashref contains an entry with
-additional values that have been calculated for that item but that
-aren't stored in the item object itself. These include C<linetotal>,
-C<linetotal_cost>, C<sellprice>, C<tax_amount> and C<taxkey>.
+An array reference. For each line item this array contains a hash ref
+entry with additional values that have been calculated for that item
+but that aren't stored in the item object itself. These include
+C<linetotal>, C<linetotal_cost>, C<sellprice>, C<tax_amount> and
+C<taxkey_id>.