Here is a trick/workaround you can try:
Create a Section for the Detail with the Horizontal Depth settings you want, then create the Detail Marker in that Section.
The Section would be limited both horizontally and vertically to show just the portion you need in the Detail. You may even place the Section line on a hidden layer.
When there is a change in the model, you can go to the Section, Regenerate it, then go to the Detail and regenerate that based on the Section.
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