All conversions are carried out in real-time and the converted data is only stored in memory. This means that no data is stored in the portal, and after the 15-minute period it will be flushed. This is a security measure, but it also applies if you have been inactive for a 15-minute period after uploading your files to the Converter and/or Inspector.
If the data is flushed before you have downloaded the converted files, you will need to start the conversion over in order to download the resulting iXBRL file.