Today, Inline XBRL Viewers are pretty rudimentary in terms of functionality. Over time that will change.
Here are some Inline XBRL files where a viewer is not used: (they basically look like normal HTML documents)
Here are some Inline XBRL files where a viewer IS USED:
What would be really nice is if someone got inspired or saw the business opportunity and created a really good Inline XBRL Viewer. That will eventually happen.
The SEC Inline Viewer is open source I believe. I do know you can get the source code for an Inline Viewer that is provide by the CAFR demonstration project. Arelle also provides source code for an Inline XBRL Viewer.
You can put these four files into any Inline XBRL document and you get a very basic viewer: (these links will open in Google Chrome, not so much if you use IE)
Using that information, maybe someone that is motivated can figure out how to create a better Inline XBRL Viewer. If you want to do that and need some help, please let me know and I can explain some really useful functionality. There are lots of possibilities.
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People made me aware of this information related to Inline XBRL Viewers:
Imagine a financial statement viewer that worked like this.
This is a nicely formated report but not Inline XBRL (i.e. not machine readable). What if that nice formatting was combined with Inline XBRL.