Indenting a Non-row Item in a Detail Configuration Header

The following example demonstrates how to add a non-row item that will act as a detail separator to the header section of a detail configuration whose indentation will correspond to detail and group levels in which it is contained.

<Grid xmlns:xcdg="http://schemas.xceed.com/wpf/xaml/datagrid"
      xmlns:local="clr-namespace:Xceed.Wpf.Documentation">
  <Grid.Resources>
   <xcdg:DataGridCollectionViewSource x:Key="cvs_employees"
                                      Source="{Binding Source={x:Static Application.Current},
                                                Path=Employees}"/>
 
  </Grid.Resources>
 
  <xcdg:DataGridControl x:Name="EmployeesGrid"
                        ItemsSource="{Binding Source={StaticResource cvs_employees}}"
                        AutoCreateDetailConfigurations="True">  
     <xcdg:DataGridControl.Columns>
        <xcdg:Column FieldName="Photo"
                     Visible="False" />
     </xcdg:DataGridControl.Columns>
     <xcdg:DataGridControl.DetailConfigurations>
        <xcdg:DetailConfiguration RelationName="Employee_Orders"
                                  Title="Employee Orders"
                                  UseDefaultHeadersFooters="False">
           <xcdg:DetailConfiguration.Headers>
              <DataTemplate>
                 <DockPanel>                                   
                    <xcdg:HierarchicalGroupLevelIndicatorPane  xcdg:GroupLevelIndicatorPane.ShowIndicators="False"
                                                               xcdg:TableView.CanScrollHorizontally="False"
                                                                DockPanel.Dock="Left" />
                    <Border Height="24"
                            xcdg:TableView.CanScrollHorizontally="False"
                            Background="AliceBlue"/>
                 </DockPanel>
              </DataTemplate> 
             <DataTemplate>
                 <xcdg:ColumnManagerRow />
              </DataTemplate>
           </xcdg:DetailConfiguration.Headers>
        </xcdg:DetailConfiguration>
     </xcdg:DataGridControl.DetailConfigurations>       
  </xcdg:DataGridControl>
</Grid>