function throbber_show()
{
	if ( document.getElementById( 'throbber' ) )
		document.getElementById( 'throbber' ).style.display = 'block' ;
}

function throbber_hide()
{
	if ( document.getElementById( 'throbber' ) )
		document.getElementById( 'throbber' ).style.display = 'none' ;
}