function doShowHide(pPositionName)
{
	var bCurrentlyShowing = ((document.getElementById(pPositionName).style.display=='none')?true:false);
	var TheThTags = document.getElementsByTagName('th');
	for(var i = 0; i <  TheThTags.length; i++)
		if(TheThTags[i].className == pPositionName && TheThTags[i].id != '')
			document.getElementById('tr' + TheThTags[i].id).style.display = ((bCurrentlyShowing)? 'none' : '');
	document.getElementById(pPositionName).style.display = ((bCurrentlyShowing)? '': 'none');
}