wp_list_categories not excluing multiple ids

I’m pretty sure this is a Codex error and that the string that exclude parameter expects for wp_list_categories() is really meant for non-hierarchical tags, such as blue,red where hierarchical you need to pass an array of integers:

$args = array(
    'orderby'            => 'ID',
    'show_count'         => 1,
    'taxonomy'           => 'portfolio-type',
    'use_desc_for_title' => 1,
    'echo'               => 0,
    'title_li'           => '',
    'exclude'            => array( 115, 161 ),
);
wp_list_categories( $args );

Always cross reference The Codex with Developer Resources!