<cfscript>
    function formatPhone( required string phoneNumber ){
        var phone = reReplace( arguments.phoneNumber, "[^[:digit:]]", "", "all" );
        phone = right( phone, 10 );

        if ( phone.len() >= 7 ){
            phone = insert( '-', phone, 6) ;
            phone = insert( '-', phone, 3) ;
        }
        return phone;
    }

    writeDump( formatPhone( "+16305670001" )  );
</cfscript>