Is there a document besides the one you have to buy from the AIA that indicates which pen color and width are to go with each layer? Is there a document which indicates the pen widths in the AIA standard plot styles? I like the ADT setup the layers but it would be nice to have some documentation of what you are working with.
The US National CAD Standard, which incorporates the AIA Layer Guidelines, does not assign colors to layers. The Uniform Drawing System, also part of the US NCS, does indicate lineweights that should be used in general and also for certain specific items [mostly annotation]. The Tri-Service Plotting Guidelines - the third component of the US NCS - has a chart that maps drawing colors to plotted color, lineweight and screening. The ADT team developed one possible way of conforming to all of that [and filled in any gaps as needed].
As for documentation of the ADT settings, you can reverse engineer that by looking at the layer key style and plot styles. For monochrome plotting, take a look at the "AIA Standard.ctb" file - in one place, that will show you the color-lineweight-screening relationships used in the out-of-the-box settings. [Even if you use named plot styles and assign lineweights in the drawing, you will find that those relationships hold. For example, layer A-Wall is color 113, 0.50 mm lineweight and 100% screening. You will find that the "AIA" layer key style sets up layer A-Wall with that lineweight, should you be assigning the lineweight in the drawing.]