protected function _fromSequenceString($str)
    {
        $ids = array();
        $str = trim($str);

        if (!strlen($str)) {
            return $ids;
        }

        $idarray = explode(',', $str);

        foreach ($idarray as $val) {
            $range = explode(':', $val);
            if (isset($range[1])) {
                for ($i = min($range), $j = max($range); $i <= $j; ++$i) {
                    $ids[] = $i;
                }
            } else {
                $ids[] = $val;
            }
        }

        return $ids;
    }