This question is particularly interesting in Denny's example, as the Class E extends up to and including 17,999' MSL. In the Class D situations, at least there's a top around 2,500' AGL...
Wouldn't the airspace above the top of the Class D be Class E, or higher? I wouldn't think there would be any situations where it is not within the CONUS. (Though I have seen it at remote islands in the middle of oceans, i.e. FJDG and FHAW)
Larry -- No Class D in Denny's example. It's a Class E surface area, so the overlying airspace (assuming not restricted or prohibited) is Class A, above 17,999' MSL.