code: function (subViews) {
              subViews = subViews || this.subViews;
  
              var i = -1;
              var len = subViews.length;
              while (++i < len) {
                  subViews[i].$el.detach();
              }
              return this;
          }
docs: Shortcut method to invoke jQuery's detach function
  on each of the '.$el' elements for each of the
  subviews, or if an array of subViews is passed,
  on each of those. Useful if you want to re-render
  a parent view and want to prevent subviews from
  losing their events and other data that is removed
  when jQuery 'remove' is called on that element.
  @memberOf SubViewManager#
  @type {SubViewManager}
  @param {Backbone.View[]} subViews
  @return {SubViewManager}