private function prepareDetailsForAPI(array $details)
    {
        foreach ($details as $key => &$detailValues) {
            if (is_array($detailValues)) {
                $this->prepareDetailsForAPI($detailValues);
            }

            if ('contactSource_id' === $key) {
                // Don't include this as it should be included in parent as contactId
                unset($details[$key]);
                continue;
            }

            if (strstr($key, '_')) {
                $newKey           = lcfirst(str_replace('_', '', ucwords($key, '_')));
                $details[$newKey] = $details[$key];
                unset($details[$key]);
            }
        }

        return $details;
    }