protected function determineDetailOption() {
        if (!isset($this->options['IsPartnered']) || !isset($this->options['ShipmentType'])) {
            $this->log('Cannot set transport details without shipment type and partner parameters!', 'Warning');
            return false;
        }
        $op = 'TransportDetails.';
        if ($this->options['ShipmentType'] == 'SP') {
            if ($this->options['IsPartnered'] == 'true') {
                return $op . 'PartneredSmallParcelData';
            } else {
                return $op . 'NonPartneredSmallParcelData';
            }
        } else if ($this->options['ShipmentType'] == 'LTL') {
            if ($this->options['IsPartnered'] == 'true') {
                return $op . 'PartneredLtlData';
            } else {
                return $op . 'NonPartneredLtlData';
            }
        }
        $this->log('Unknown shipment type, cannot set transport details!', 'Warning');
        return false;
    }