The buttons do not have a Name or a value.
For the Details button, change:
<input type="button" class="formButton ResultsPageButton DetailButton" value="" onclick="document.location.href='employees_detail.php?employeeID=<?php echo($row_WADAemployees['employeeID']); ?>
<?php echo(isset($_GET["pageNum_WADAemployees"])?"&pageNum_WADAemployees=".intval($_GET["pageNum_WADAemployees"]):""); ?>';"/>
to:
<input name="details" type="button" class="formButton ResultsPageButton DetailButton" id="details" onclick="document.location.href='employees_detail.php?employeeID=<?php echo($row_WADAemployees['employeeID']); ?><?php echo(isset($_GET["pageNum_WADAemployees"])?"&pageNum_WADAemployees=".intval($_GET["pageNum_WADAemployees"]):""); ?>';" value="Details"/>
for the update button, change:
<input type="button" class="formButton ResultsPageButton UpdateButton" value="" onclick="document.location.href='employees_update.php?employeeID=<?php echo($row_WADAemployees['employeeID']); ?>
<?php echo(isset($_GET["pageNum_WADAemployees"])?"&pageNum_WADAemployees=".intval($_GET["pageNum_WADAemployees"]):""); ?>';"/><input type="button" class="formButton ResultsPageButton DeleteButton" value="" onclick="document.getElementById('WADADeleteRecordID').value=<?php echo($row_WADAemployees['employeeID']); ?>;document.getElementById('deleteBox').style.display = 'block';document.getElementById('deleteMessage').style.display = 'table';" />
to:
<input name="update" type="button" class="formButton ResultsPageButton UpdateButton" id="update" onclick="document.location.href='employees_update.php?employeeID=<?php echo($row_WADAemployees['employeeID']); ?>
<?php echo(isset($_GET["pageNum_WADAemployees"])?"&pageNum_WADAemployees=".intval($_GET["pageNum_WADAemployees"]):""); ?>';" value="Update"/>
for the delete button, change:
<input type="button" class="formButton ResultsPageButton DeleteButton" value="" onclick="document.getElementById('WADADeleteRecordID').value=<?php echo($row_WADAemployees['employeeID']); ?>;document.getElementById('deleteBox').style.display = 'block';document.getElementById('deleteMessage').style.display = 'table';" />
to:
<input name="delete" type="button" class="formButton ResultsPageButton DeleteButton" id="delete" onclick="document.getElementById('WADADeleteRecordID').value=<?php echo($row_WADAemployees['employeeID']); ?>;document.getElementById('deleteBox').style.display = 'block';document.getElementById('deleteMessage').style.display = 'table';" value="Delete" />