Now, realize that I am not a programmer. This is what I was able to do with the filings to the SEC's Next-Generation EDGAR system.
Goal/Result: The goal was to get a list of the extension concepts filers were creating and using in their filings. There is no particular purpose for this, only to do it because it is interesting and not that hard to do. Here is the result of what I was able to create. (This is the Excel spreadsheet which contains the macros, VBA that is, put into a ZIP file which you can use to see how this works.)
First off, I cheated a little. I used information made available by Cliff Binstock on his XBRL Cloud. And I actually did not use that file which is a human readable version; I used this file, which is an XML version of this same information. You can find a link to that file on the top of the human readable version.
Next, I created a simple Excel macro. Again, this spreadsheet contains those. Pretty basic, I know. Again, I am a CPA. Working with the XML is so easy and fun. The hard part is getting the information you want to work with. For example, I wanted the extension concepts. I could have grabbed these from the XBRL instance or from the XBRL taxonomy submitted with the filing. I also wanted the labels for the concept and the documentation provided by the filer so I could understand what the concept was meant to be for. Cliff made the list of concepts, their labels, and their documentation available in one location. I assumed he used his XBRL processor to put these pieces together. You could put these pieces together using plane old XML. But, it is too much work when you can simply use an XBRL processor or the pre-processed information.
I loaded the XBRL information about the extensions into the Excel spreadsheet. This information is in one spreadsheet. I looked through the information a little, highlighting a few things. I can see that filers were adding concepts such as "IncomeTax" which I would never have expected to be added. Further, particularly with that concept, there is no documentation explaining the concept.
If you understand Excel macros, but have never used XML, the code samples show you how to do this. It is really amazing how easy working with XML is. Again, the hard part are having the pieces organized in a way you would use them, NOT in the XBRL physical syntax which is too hard to work with. That is where an XBRL processor is helpful.
If you endeavor to try and create something interesting, let me know about it; I would love to see what others come up with.