This will solve your purpose. let me know if anything goes wrong.
$ids[135][0]->ID = 145;
$ids[135][1]->ID = 135;
$ids[135][2]->ID = 155;
$ids[140][0]->ID = 125;
$ids[140][1]->ID = 135;
$idss = array();
foreach($ids as $k => $v) {
for($i = 0; $i < count($v); $i++) {
if(!@$idss[$k] || $v[$i]->ID > $idss[$k])
{
$idss[$k] = $v[$i]->ID;
}
}
}
echo "<Pre>";
print_r($idss);
die;