it's because you are using the tick character "`" instead of the apostrophe or single quote chacter "'"
change your code:
<td align="center"><a href="details_page.php?id=<?php echo $row_rs_details[`id`]; ?>">Details</a></td>
to:
<td align="center"><a href="details_page.php?id=<?php echo $row_rs_details['id']; ?>">Details</a></td>