vi8 | Various bits of information on getting Linux

I downloaded 13 000 files (10-K reports from different companies) and I need to extract a specific part of these files (section 1A- Risk factors). The problem is that I can open these files in Word easily and they are perfect, while as I open them in a normal txt editor, the document appear to be an HTML with tons of encrypted string in the end (EDIT: I suspect this is due to XBRL format of these files). Same happens as a result of using BeautifulSoup.

I've tried using online decoder, because I thought that maybe this is connected to Base64 encoding, but it seems that none of the known encoding could help me. I saw that at the beginning of some files, there is something like: "created with Certent Disclosure Management 6.31.0.1" and other programs, I thought maybe this causes the encoding. Nevertheless Word is able to open these files, so I guess there must be a known key to it. This is a sample encoded data: