if (count($orderDetails) > 0) {
    $orderDetailsCount = count($orderDetails);
    $shipmentItemsCount = count($shipmentItems);
    for ($i = 0; $i < $orderDetailsCount; $i++) {
        for ($j = 0; $j < $shipmentItemsCount; $j++) {
            $itemidx = &$shipmentItems[$j]['itemidx'];
            if ($itemidx == $i) {
                $shipmentItem = &$shipmentItems[$j];
                $shipmentItem['price'] = $orderDetails[$i]['price'];
                $orderDetail = &$orderDetails[$i];
                $orderDetail['quantity'] = $shipmentItems[$j]['quantity'];
                break;
            }
        }
    }
}