var OverNav = false;
var NavOutGracePeriod = 500;
var CurrentTimerID = 0;

function NavOver( Element )
{
	var SubNav = GetNextSibling( Element, 'ul' );
	if( SubNav )
	{
		HideSubNav();
		SubNav.style.display = 'block';
		SubNav.style.position = 'absolute';
		SubNav.style.zIndex = '10';
		OverNav = true;
	}
	else
	{
		OverNav = false;
		HideSubNav();
		OverNav = true;
	}
}

function NavOut( Element )
{
	var SubNav = GetNextSibling( Element, 'ul' );
	if( SubNav )
	{
		OverNav = false;
		CurrentTimerID = window.setTimeout( "HideSubNav();", NavOutGracePeriod );
	}
}

function HideSubNav()
{
	if( !OverNav )
	{
		if( CurrentTimerID )
		{
			clearTimeout( CurrentTimerID );
			CurrentTimerID = 0;
		}
		var Nav = document.getElementById( 'Navigation_ul' );
		var SubNav = Nav.getElementsByTagName( 'ul' );
		for( i = 0; i < SubNav.length; i++ )
		{
			if( SubNav[i].style.display != 'none' )
			{
				SubNav[i].style.display = 'none';
			}
		}
	}
}

function GetNextSibling( Element, Tag )
{
	while( Element != null )
	{
		if( Element.tagName && Element.tagName.toLowerCase() == Tag.toLowerCase() )
		{
			break;
		}

		Element = Element.nextSibling;
	}

	return Element;
}