Code

<Style TargetType="{x:Type local:ResourceHeader}">
	<Setter Property="Template">
		<Setter.Value>
			<ControlTemplate TargetType="{x:Type local:ResourceHeader}">
			<Border DataContext="{Binding Path=., RelativeSource={RelativeSource TemplatedParent}}"
				Background="{Binding Settings.HeaderStyle.Background}"
				BorderBrush="{Binding Settings.HeaderStyle.BorderBrush}"
				BorderThickness="{Binding Settings.HeaderStyle.BorderThickness}">
				<Grid>
					<Grid.ColumnDefinitions>
						<ColumnDefinition Width="Auto" />
						<ColumnDefinition />
					</Grid.ColumnDefinitions>
					<local:ExpanderControl
						Name="expander" IsExpanded="{Binding IsExpanded, Mode=TwoWay}"
						Width="11" Height="11" Margin="2" VerticalAlignment="Top"
						BorderBrush="{Binding Settings.HeaderStyle.LineBrush}"
						Background="{Binding Settings.CalendarStyle.Background}"
						BorderThickness="1"
						Foreground="{Binding Settings.HeaderStyle.LineBrush}"
						Visibility="{Binding Settings.ExpandableRows, Converter={StaticResource visibleConverter}, ConverterParameter=True}"/>
					<TextBlock Grid.Column="1"
						Text="{Binding Converter={StaticResource resourceNameConverter}}"
						FontFamily="{Binding Settings.HeaderStyle.FontFamily}"
						FontSize="{Binding Settings.HeaderStyle.FontSize}"
						FontStretch="{Binding Settings.HeaderStyle.FontStretch}"
						FontStyle="{Binding Settings.HeaderStyle.FontStyle}"
						FontWeight="{Binding Settings.HeaderStyle.FontWeight}"
						Foreground="{Binding Settings.HeaderStyle.Foreground}"
						TextAlignment="{Binding Settings.HeaderStyle.TextAlignment}"
						HorizontalAlignment="{Binding Settings.HeaderStyle.HorizontalAlignment}"
						VerticalAlignment="{Binding Settings.HeaderStyle.VerticalAlignment}"
						Margin="{Binding Settings.HeaderStyle.ContentMargin}"
						TextWrapping="Wrap" />
					</Grid>
				</Border>
			</ControlTemplate>
		</Setter.Value>
	</Setter>
</Style>