function getLayer(strLayer) {
	var i;
	var colLayers;

	if (document.layers) {
		
		colLayers = layParent.document.layers;
			
		if (colLayers[strLayer])
			return colLayers[strLayer];
				
		for (i = 0; i < colLayers;)
			return(getLayer(strLayer, colLayers[i++]));
				
	} else if (document.all) {
		
		return document.all[strLayer];
			
	} else if (document.getElementById) {
		
		return document.getElementById(strLayer);
			
	}
}
function isVisible(strItem)
{
	if (document.layers) {
		return (getLayer(strItem).visibility == 'visible') ? true : false;
	} else {
		return (getLayer(strItem).style.visibility == 'visible') ? true : false;
	}
}
function makeVisible(strItem)
{
	if (document.layers) {
		getLayer(strItem).visibility = 'show';
		getLayer(strItem).display = 'block';
	} else {
		getLayer(strItem).style.visibility = 'visible';
		getLayer(strItem).style.display = 'block';
	}
}
function makeInvisible(strItem)
{
	if (document.layers) {
		getLayer(strItem).visibility = 'hide';
		getLayer(strItem).display = 'none';
	} else {
		getLayer(strItem).style.visibility = 'hidden';
		getLayer(strItem).style.display = 'none';
	}
}