How do I query based on the modified date?

Question

I would like to list posts by the "modified" date not the published date. Is there a way to do this?

        $documents = array('posts_per_page' => 10, 'post_type' => 'documents',);
        query_posts( $documents );
        get_template_part( 'loop', 'docid' );
        wp_reset_query();

Answer 1

http://codex.wordpress.org/Class_Reference/WP_Query#Order_.26_Orderby_Parameters

'orderby' => 'modified'