Facetapi slider + Apachesolr term not want to work together

implemented online search taxonomy terms, each term has a number of fields in which I have made custom facets, and one of them:

    $facets['enrollment'] = array(
      'label' => t('Total student population'),
      'description' => t('Filter by student population.'),
      'field' => 'itm_field_univ_enrollment',
      'query type' => 'numeric_range',
      'dependency plugins' => array('role'),
    );

Display has widget: Slider
and does not appear on the search page.
I hope you can help me, thanks.