PasswordBox does not apply style

I have the following style definitions:

<!-- Border -->
<Style x:Key="MyControlBorder" TargetType="{x:Type Border}">
    <Setter Property="BorderBrush" Value="DarkKhaki" />
    <Setter Property="Background" Value="White" />
    <Setter Property="BorderThickness" Value="1" />
    <Setter Property="CornerRadius" Value="10" />
</Style>

<!-- TextBox -->
<Style x:Key="MyTextBox" TargetType="{x:Type TextBox}">
    <Setter Property="Height" Value="30" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type TextBoxBase}">
                <Border Name="TextBoxBorder" Style="{StaticResource MyControlBorder}">
                    <ScrollViewer x:Name="PART_ContentHost"/>
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

<!-- PasswordBox -->
<Style x:Key="MyPasswordBox" TargetType="{x:Type PasswordBox}">
    <Setter Property="Height" Value="30" />
    <Setter Property="Template">
        <Setter.Value>
            <ControlTemplate TargetType="{x:Type Control}">
                <Border Name="Border" Style="{StaticResource MyControlBorder}">
                    <ScrollViewer x:Name="PART_ContentHost" />
                </Border>
            </ControlTemplate>
        </Setter.Value>
    </Setter>
</Style>

And the following XAML code:

<Grid>
    <Grid.RowDefinitions>
        <RowDefinition Height="*" />
        <RowDefinition