IsDocument Property not set when using CSOM

I'm using CSOM with C# to upload a file to SharePoint 2013 using the SaveBinaryDirect method as defined in the MSDN reference for example the following:

File.SaveBinaryDirect(context, filePath, fileStream, false);
File.CheckIn(versionComment, CheckinType.MajorCheckIn);

But, when I search for it with IsDocument:1 Search does not find it but if I change the search text to IsDocument:0 Search does find it.  It does find a document that I upload directly to the SharePoint web site via browser.  I don't see anywhere in the MSDN CSOM reference where there is some method or property that needs to be set in order for IsDocument to be set by SharePoint.  Anybody have a clue?