First, you want to link your details into a Drafting view, not a Callout - Detail View, unless you meant by Detail view, Drafting view. If you import your DWG details into a Callout - Detail view the scale of the hatch patterns will not necessarly read correctly at the correct scale.
You could Region Fill over the DWG hatch patterns and/or eliminate all hatch patterns by layer on importing the DWG, but importing the DWG into a Dafting view will be more successful.
Mel Persin, AIA
AEC Technology Consultant
Technology to Visualize and Realize Solutions
Reporting from Autodesk University 2007
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